fix(EVO-2178): validate incoming media URLs before fetching them - #6
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Review follow-up to EVO-2180. Attachment URLs arrive inside the /events payload and the adapter fetched them verbatim, so the endpoint doubled as a read primitive aimed by its caller: the bytes of any URL reachable from this service were base64-encoded into the A2A call, whose destination (outgoing_url) comes from the same payload. Reproduced end to end against a local metadata-style endpoint, both directly and through a 302. - checkMediaURL pins the scheme to http/https and requires the host to be one the CRM is known to serve blobs from: the postback URL's host (already mandatory in MessageEvent.Validate, so no new config for the default topology) plus whatever MEDIA_HOST_ALLOWLIST names, for deployments serving blobs off an S3/MinIO/CDN host. Unauthorized media is skipped and logged; the text reply is unaffected, like every other media failure here. - The download client re-runs that check on every redirect hop, so an authorized host cannot walk the fetch onto an internal address. - BOT_RUNTIME_SECRET becomes required. It was read with os.Getenv, and SecretMiddleware compares the header against it, so an empty value authenticated every caller that simply omitted the header. - The media buffer key gets a TTL. ClearState remains the normal cleanup; the TTL only stops a turn that dies before reaching it from leaving media URLs in Redis forever. - Attachment download failures now log the HTTP status: the common production case is a 404 from a signed link that expired while the queue was backed up, and it read identically to an unreachable host. - Adds .github/workflows/ci.yml. Nothing ran the Go suite on a PR, which is how test/e2e stayed non-compiling from EVO-558 until EVO-2180.
Reviewer's GuideThis PR hardens media handling in the AI adapter to prevent SSRF/exfiltration, enforces a non-empty bot runtime secret, bounds the lifetime of Redis media buffers, improves logging of media download failures, and adds a CI workflow that runs the Go build/vet/test suite on pushes and PRs. Sequence diagram for validated media download with SSRF protectionsequenceDiagram
participant PipelineService
participant AIAdapter
participant MediaClient
participant MediaHost
PipelineService->>AIAdapter: runAIStage(...)
AIAdapter->>AIAdapter: allowedMediaHosts(PostbackURL)
AIAdapter->>AIAdapter: mediaClient(hosts)
loop for each Attachment
AIAdapter->>AIAdapter: checkMediaURL(Attachment.URL, hosts)
alt URL not allowed
AIAdapter->>AIAdapter: slog.Warn("pipeline.ai.attachment.blocked_url")
else URL allowed
AIAdapter->>MediaClient: downloadAttachment(ctx, client, URL, timeout, limit)
activate MediaClient
MediaClient->>MediaHost: GET URL
alt Redirect response
MediaHost-->>MediaClient: 3xx Location
MediaClient->>MediaClient: CheckRedirect(...)
MediaClient->>AIAdapter: checkMediaURL(newURL, hosts)
alt checkMediaURL fails
MediaClient-->>AIAdapter: error
else checkMediaURL ok
MediaClient->>MediaHost: GET newURL
end
else 200 OK
MediaHost-->>MediaClient: 200 OK body
MediaClient-->>AIAdapter: data, contentType
else Non-200
MediaHost-->>MediaClient: status != 200
MediaClient-->>AIAdapter: &httpStatusError
end
deactivate MediaClient
alt error from downloadAttachment
AIAdapter->>AIAdapter: statusOf(err)
AIAdapter->>AIAdapter: slog.Warn("pipeline.ai.attachment.download_failed")
else success
AIAdapter->>AIAdapter: append file part
end
end
end
Flow diagram for media host allowlist and Redis attachment TTLflowchart LR
subgraph MediaAllowlist
A[PostbackURL] -->|hostname| B[allowedMediaHosts]
C[MEDIA_HOST_ALLOWLIST] -->|comma-separated hosts| B
B --> D{hosts map empty?}
D -->|yes| E[All attachments skipped<br/>fail-closed]
D -->|no| F["checkMediaURL(rawURL, hosts)"]
F -->|invalid/unauthorized| G[blocked_url log]
F -->|ok| H[downloadAttachment]
end
subgraph RedisBufferTTL
I[AppendAttachments] --> J[RPush attachBufferKey]
J --> K[Expire attachBufferKey<br/>attachBufferTTL]
end
File-Level Changes
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Hey - I've found 2 issues
Prompt for AI Agents
Please address the comments from this code review:
## Individual Comments
### Comment 1
<location path="pkg/ai/service/ai_adapter.go" line_range="500-510" />
<code_context>
+// transport (connection pool) but re-runs checkMediaURL on every redirect hop: an
+// allowlisted host that answers 302 must not be able to walk the download onto a
+// link-local or internal address.
+func (a *aiAdapter) mediaClient(hosts map[string]struct{}) *http.Client {
+ return &http.Client{
+ Transport: a.client.Transport,
+ CheckRedirect: func(req *http.Request, via []*http.Request) error {
+ if len(via) >= 10 {
+ return errors.New("stopped after 10 redirects")
+ }
+ return checkMediaURL(req.URL.String(), hosts)
+ },
+ }
+}
+
</code_context>
<issue_to_address>
**suggestion (bug_risk):** mediaClient drops http.Client-level settings from a.client; consider reusing or cloning the existing client.
This creates a new http.Client that only reuses a.client.Transport and adds CheckRedirect, dropping any other configuration on a.client (e.g., CookieJar, Timeout, etc.) for media downloads.
Consider either:
- Basing mediaClient on a.client and overriding only CheckRedirect, or
- Clearly documenting that mediaClient is intentionally configured differently.
This avoids surprises if a.client is later updated (e.g., global Timeout or Jar) with the expectation that media downloads share those settings.
```suggestion
func (a *aiAdapter) mediaClient(hosts map[string]struct{}) *http.Client {
// Clone the base client so media downloads inherit all configuration
// (timeouts, cookie jar, etc.) but enforce our own redirect policy.
clientCopy := *a.client
clientCopy.CheckRedirect = func(req *http.Request, via []*http.Request) error {
if len(via) >= 10 {
return errors.New("stopped after 10 redirects")
}
return checkMediaURL(req.URL.String(), hosts)
}
return &clientCopy
}
```
</issue_to_address>
### Comment 2
<location path="pkg/pipeline/repository/redis_pipeline_repository.go" line_range="89-93" />
<code_context>
values = append(values, b)
}
- return r.rdb.RPush(ctx, attachBufferKey(contactID, conversationID), values...).Err()
+ key := attachBufferKey(contactID, conversationID)
+ if err := r.rdb.RPush(ctx, key, values...).Err(); err != nil {
+ return err
+ }
+ // ClearState is the normal cleanup, but any turn that dies without reaching it
+ // (panic, killed pod, a Redis blip on the Del) would otherwise leave this key —
+ // and the media URLs in it — in Redis forever. The TTL is a floor, not the
+ // debounce window: it only has to outlive the longest possible turn.
+ return r.rdb.Expire(ctx, key, attachBufferTTL).Err()
}
</code_context>
<issue_to_address>
**suggestion (bug_risk):** TTL failure now makes AppendAttachments fail; consider whether this should be best-effort instead of hard-fail.
With this change, any transient Expire failure (e.g., network blip, Redis failover) will cause AppendAttachments to return an error even though RPush has already succeeded and the data is durably written.
Since attachBufferTTL is a safety net rather than a correctness requirement, consider treating Expire as best-effort: log on failure but still return nil when RPush succeeds, so the main write path doesn’t gain new failure modes solely due to TTL issues.
```suggestion
// ClearState is the normal cleanup, but any turn that dies without reaching it
// (panic, killed pod, a Redis blip on the Del) would otherwise leave this key —
// and the media URLs in it — in Redis forever. The TTL is a floor, not the
// debounce window: it only has to outlive the longest possible turn.
//
// Expire is best-effort: a failure here should not turn a successful append
// into an error, since the TTL is a safety net rather than a correctness
// requirement.
_ = r.rdb.Expire(ctx, key, attachBufferTTL).Err()
return nil
```
</issue_to_address>Help me be more useful! Please click 👍 or 👎 on each comment and I'll use the feedback to improve your reviews.
Comment on lines
+500
to
+510
| func (a *aiAdapter) mediaClient(hosts map[string]struct{}) *http.Client { | ||
| return &http.Client{ | ||
| Transport: a.client.Transport, | ||
| CheckRedirect: func(req *http.Request, via []*http.Request) error { | ||
| if len(via) >= 10 { | ||
| return errors.New("stopped after 10 redirects") | ||
| } | ||
| return checkMediaURL(req.URL.String(), hosts) | ||
| }, | ||
| } | ||
| } |
There was a problem hiding this comment.
suggestion (bug_risk): mediaClient drops http.Client-level settings from a.client; consider reusing or cloning the existing client.
This creates a new http.Client that only reuses a.client.Transport and adds CheckRedirect, dropping any other configuration on a.client (e.g., CookieJar, Timeout, etc.) for media downloads.
Consider either:
- Basing mediaClient on a.client and overriding only CheckRedirect, or
- Clearly documenting that mediaClient is intentionally configured differently.
This avoids surprises if a.client is later updated (e.g., global Timeout or Jar) with the expectation that media downloads share those settings.
Suggested change
| func (a *aiAdapter) mediaClient(hosts map[string]struct{}) *http.Client { | |
| return &http.Client{ | |
| Transport: a.client.Transport, | |
| CheckRedirect: func(req *http.Request, via []*http.Request) error { | |
| if len(via) >= 10 { | |
| return errors.New("stopped after 10 redirects") | |
| } | |
| return checkMediaURL(req.URL.String(), hosts) | |
| }, | |
| } | |
| } | |
| func (a *aiAdapter) mediaClient(hosts map[string]struct{}) *http.Client { | |
| // Clone the base client so media downloads inherit all configuration | |
| // (timeouts, cookie jar, etc.) but enforce our own redirect policy. | |
| clientCopy := *a.client | |
| clientCopy.CheckRedirect = func(req *http.Request, via []*http.Request) error { | |
| if len(via) >= 10 { | |
| return errors.New("stopped after 10 redirects") | |
| } | |
| return checkMediaURL(req.URL.String(), hosts) | |
| } | |
| return &clientCopy | |
| } |
Comment on lines
+89
to
+93
| // ClearState is the normal cleanup, but any turn that dies without reaching it | ||
| // (panic, killed pod, a Redis blip on the Del) would otherwise leave this key — | ||
| // and the media URLs in it — in Redis forever. The TTL is a floor, not the | ||
| // debounce window: it only has to outlive the longest possible turn. | ||
| return r.rdb.Expire(ctx, key, attachBufferTTL).Err() |
There was a problem hiding this comment.
suggestion (bug_risk): TTL failure now makes AppendAttachments fail; consider whether this should be best-effort instead of hard-fail.
With this change, any transient Expire failure (e.g., network blip, Redis failover) will cause AppendAttachments to return an error even though RPush has already succeeded and the data is durably written.
Since attachBufferTTL is a safety net rather than a correctness requirement, consider treating Expire as best-effort: log on failure but still return nil when RPush succeeds, so the main write path doesn’t gain new failure modes solely due to TTL issues.
Suggested change
| // ClearState is the normal cleanup, but any turn that dies without reaching it | |
| // (panic, killed pod, a Redis blip on the Del) would otherwise leave this key — | |
| // and the media URLs in it — in Redis forever. The TTL is a floor, not the | |
| // debounce window: it only has to outlive the longest possible turn. | |
| return r.rdb.Expire(ctx, key, attachBufferTTL).Err() | |
| // ClearState is the normal cleanup, but any turn that dies without reaching it | |
| // (panic, killed pod, a Redis blip on the Del) would otherwise leave this key — | |
| // and the media URLs in it — in Redis forever. The TTL is a floor, not the | |
| // debounce window: it only has to outlive the longest possible turn. | |
| // | |
| // Expire is best-effort: a failure here should not turn a successful append | |
| // into an error, since the TTL is a safety net rather than a correctness | |
| // requirement. | |
| _ = r.rdb.Expire(ctx, key, attachBufferTTL).Err() | |
| return nil |
gomessguii
added a commit
that referenced
this pull request
Aug 28, 2026
* fix(EVO-2167): retry the AI Processor call on transient failures The bot-runtime made a single call to the AI Processor: any non-200 (401/5xx) or network error aborted the pipeline and the customer's message was dropped with no reply and no retry (only AI_CALL_TIMEOUT_SECONDS existed). A momentary blip — deploy, restart, DB hiccup — meant a permanently lost answer. - ai_adapter.go: extract a single attempt into doOnce() and wrap Call() in a retry loop with exponential backoff + jitter. Retryable: network errors and 429/500/502/503/504. NOT retried: 4xx (permanent), per-attempt timeout, pipeline cancellation. Body is built once and reused per attempt. - config.go: AI_CALL_MAX_RETRIES (default 2) and AI_CALL_RETRY_BASE_MS (default 200). - main.go: wire the new config into NewAIAdapter. - tests: 503->200 retry succeeds (2 calls); persistent 500 exhausts retries (1+2 calls); 400 not retried (1 call); network error then success (2 calls); maxRetries=0 disables retry. Existing tests updated to the new signature (0 retries). Complements EVO-2166: the processor now returns 503 (not a silent 401) on infra errors, so this retry covers the transient auth/infra case. Root cause of the incident is EVO-2141 (pool_pre_ping, already merged); this is defense in depth. Note: test/e2e/e2e_test.go was already incompatible with NewAIAdapter on develop (pre-existing, unrelated) and is left as-is; repo CI is docker-only (no go test lane). * fix(EVO-2167): harden retry — total-time cap + per-attempt timeout test Review follow-ups on the AI Processor retry path: - Add an overall time-budget backstop so the retry loop is provably bounded ((attempts+1) x per-attempt timeout + summed max backoff); the +1 slack keeps a per-attempt timeout surfacing as ErrAITimeout instead of being swallowed by the backstop. AC "teto de tempo total". - Add TestCall_TimeoutIsNotRetried: a per-attempt timeout must return ErrAITimeout and must NOT be retried with retries enabled. AC #5 "timeout por tentativa". - Document the idempotency contract on the retry path (502/504/network replay can re-run an already-processed turn; customer still gets one reply; dedupe of the duplicate server-side turn is the AI Processor's job, tracked in EVO-2166). * feat(EVO-2180): forward incoming media to the AI Processor as A2A file parts The bot only ever sent a text part, so images/audio the customer sent never reached the AI (the agent replied "No content to process"). Accept attachments on the inbound event, carry them through the debounce window, download each and send it as a base64 A2A file part. Part of EVO-2178 (image end-to-end). - pipeline/model: MessageEvent.Attachments + Attachment{URL,ContentType,FileType}. - pipeline/repository: AppendAttachments/GetAttachments on a parallel Redis list (bot_runtime:attach:{contact}:{conv}), aggregated like the text buffer and cleared together in ClearState (no stale media leaks into the next turn). - debounce/service: Start/Reset accept attachments; GetAttachments added. - pipeline/service: thread event.Attachments through start/skip/reset/advance -> the A2ARequest (read fresh from Redis at stage launch, like the buffer). - ai/model: A2ARequest.Attachments; JSONRPCPart.File + JSONRPCFile{Name,MimeType,Bytes} (tags match the processor's extract_files_from_message). - ai/service/ai_adapter: download each attachment once (before Marshal, reused across retries) with a 15 MiB cap; base64-encode; append a file part. A download failure is logged and skipped so the text-only message always survives. - tests: adapter forwards a file part with decodable base64 + download-failure sends text only; repo AppendAttachments/GetAttachments roundtrip + ClearState clears the attach key. Full suite green (go build/vet/test ./pkg/... ./internal/...). Note: test/e2e was already incompatible with NewAIAdapter on develop (pre-existing); repo CI is docker-only. * fix(EVO-2180): bound media forwarding and validate what is forwarded Review follow-ups on the incoming-media path. The per-file cap was the only bound, so the failure modes it did not cover fell back on the customer losing the whole reply instead of just the media. - Shared byte budget (20 MiB) across every attachment of the call. The debounce window aggregates the media of all its messages, so a photo burst built a body of len(attachments) x 15 MiB; base64 pushed that past the gateway's client_max_body_size and the resulting 413 is not retryable, killing the text reply too. Probe: 20 x 2 MiB went from a 53 MiB request to 26 MiB. - Dedicated download timeouts. Downloads run before the AI call and outside its retry ceiling, but reused AI_CALL_TIMEOUT_SECONDS (30s) per attachment, so an unreachable media host stalled the turn by 30s x len(attachments) with no bound. Now 10s per download and 30s for the whole set. - Resolve the mime type from the bytes in hand: the response Content-Type wins, then the CRM's declared type, then the URL extension. The processor feeds this straight into Blob(mime_type=...), so an HTML error/login page answered with 200 was being forwarded as a valid image, and a missing content_type became application/octet-stream. Both are now dropped or resolved. - A Redis failure on the attachment buffer no longer aborts the turn: media is best-effort everywhere else in this path, and dropping the text reply over it contradicted the card's own acceptance criterion. Tests: the event -> debounce -> Redis -> A2ARequest seam had no coverage (the debounce mock always returned nil attachments), so a refactor could silently drop the media; two pipeline tests now pin it, including aggregation across the debounce window. Adapter tests cover the byte budget, the time budget, HTML responses, oversize files and the mime resolution table. Also repairs test/e2e, which has not compiled since EVO-2167 changed NewAIAdapter/NewDispatchEngine — which is why `go vet ./...` and `go test ./...` could not be run at all. Two assertions had drifted: the message signature moved to a prefix on the first segment in EVO-558, and the state-leak check raced the cleanup goroutine it was asserting on. go build ./... && go vet ./... && go test ./... green, e2e included. * fix(EVO-2178): validate incoming media URLs before fetching them Review follow-up to EVO-2180. Attachment URLs arrive inside the /events payload and the adapter fetched them verbatim, so the endpoint doubled as a read primitive aimed by its caller: the bytes of any URL reachable from this service were base64-encoded into the A2A call, whose destination (outgoing_url) comes from the same payload. Reproduced end to end against a local metadata-style endpoint, both directly and through a 302. - checkMediaURL pins the scheme to http/https and requires the host to be one the CRM is known to serve blobs from: the postback URL's host (already mandatory in MessageEvent.Validate, so no new config for the default topology) plus whatever MEDIA_HOST_ALLOWLIST names, for deployments serving blobs off an S3/MinIO/CDN host. Unauthorized media is skipped and logged; the text reply is unaffected, like every other media failure here. - The download client re-runs that check on every redirect hop, so an authorized host cannot walk the fetch onto an internal address. - BOT_RUNTIME_SECRET becomes required. It was read with os.Getenv, and SecretMiddleware compares the header against it, so an empty value authenticated every caller that simply omitted the header. - The media buffer key gets a TTL. ClearState remains the normal cleanup; the TTL only stops a turn that dies before reaching it from leaving media URLs in Redis forever. - Attachment download failures now log the HTTP status: the common production case is a 404 from a signed link that expired while the queue was backed up, and it read identically to an unreachable host. - Adds .github/workflows/ci.yml. Nothing ran the Go suite on a PR, which is how test/e2e stayed non-compiling from EVO-558 until EVO-2180. * style(EVO-2180): trim the comments to what is not obvious from the code * fix(EVO-2178): take the media host allowlist from config, not from the event Fixes a regression I introduced in #6. The allowlist was anchored on the host of the event's postback_url, which never matches the host the CRM actually signs media URLs with: postback_url comes from BOT_RUNTIME_POSTBACK_BASE_URL (internal DNS, "evo-crm" in the shipped compose) while the URL is built from ACTIVE_STORAGE_URL, falling back to BACKEND_URL — which production requires to be a public host. So on develop every attachment was rejected as blocked_url and the agent stopped seeing images: the EVO-2178 bug, back. Anchoring on the event was also the wrong shape for the guard. Whoever sends the event chooses every field in it, including the one being used to decide what that same event may reach, so the check constrained nobody it needed to. Reading MEDIA_HOST_ALLOWLIST only puts the decision with the operator, where it cannot be chosen by the caller. A2ARequest.PostbackURL is dropped again. The scheme check and the per-redirect re-check are unchanged. This makes the variable required wherever media is expected: unset means no attachment is fetched. The deploy surfaces are wired up in the umbrella PR; k8s/configmap.yaml and k8s/deployment.yaml carry it here. * Merge pull request #9 from evolution-foundation/fix/CRM-236-degraded-provider-feedback fix(pipeline): tell the customer when the AI backend fails (CRM-236) --------- Co-authored-by: Matheus Pastorini <matheus.pastorini@etus.com.br> Co-authored-by: Matheus Pastorini <pastorinimatheus@gmail.com>
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Review follow-up to EVO-2180 (PR #5, already merged). Findings from the EVO-2178 review of the merged media path.
🔴 SSRF with exfiltration (critical)
Attachment URLs arrive inside the
/eventspayload and the adapter fetched them verbatim — no scheme check, no host check, and the client followed redirects. So/eventsdoubled as a read primitive aimed by its caller: the bytes of any URL reachable from this service were base64-encoded into the A2A call, whose destination (outgoing_url) comes from the same payload. Reproduced end to end against a local metadata-style endpoint, directly and through a302.checkMediaURLpins the scheme tohttp/httpsand requires the host to be one the CRM is known to serve blobs from: the host of the event's ownpostback_url(already mandatory inMessageEvent.Validate, so no new config for the default topology) plus whateverMEDIA_HOST_ALLOWLISTnames, for deployments serving blobs off an S3/MinIO/CDN host. Unauthorized media is skipped and logged; the text reply is unaffected, like every other media failure here.Also in this PR
BOT_RUNTIME_SECRETis now required. It was read withos.Getenv, andSecretMiddlewarecompares the header against it, so an empty value authenticated every caller that simply omitted the header.ClearStateremains the normal cleanup; the TTL only stops a turn that dies before reaching it from leaving media URLs in Redis forever.404from a signed link that expired while the queue was backed up, and it read identically to an unreachable host..github/workflows/ci.yml. Nothing ran the Go suite on a PR, which is howtest/e2estayed non-compiling from EVO-558 until EVO-2180.Verification
go build ./...·go vet ./...·go test ./...— green, e2e included, against a throwaway Redis. The new SSRF tests were mutation-checked: with the guard disabled, 3 of the 5 fail (the URL check, the redirect re-check, the fail-closed default), so they are not vacuous.Part of EVO-2178 · follow-up to EVO-2180.
🤖 Generated with Claude Code
Summary by Sourcery
Harden media handling in the AI adapter to prevent SSRF and ensure only trusted hosts and schemes are used when downloading attachments, while preserving text responses when media is blocked or fails.
Bug Fixes:
Enhancements:
CI:
Tests: