fix(webhook): enforce chunked body limits by Gutslabs · Pull Request #3955 · NousResearch/hermes-agent

Gutslabs · 2026-03-30T13:04:34Z

What does this PR do?

Fixes webhook payload size enforcement for chunked requests.

Previously, the webhook adapter only rejected oversized payloads when Content-Length was present and over the configured max_body_bytes. Chunked requests omit Content-Length, so an oversized webhook body could still be fully read and accepted.

This change enforces the same limit for chunked bodies by configuring aiohttp's client_max_size, mapping HTTPRequestEntityTooLarge to a clean 413 response, and keeping a post-read size check as a defensive fallback.

Type of Change

Bug fix
Security fix
Tests

Changes Made

Set client_max_size on the webhook aiohttp app from max_body_bytes
Return 413 Payload too large when request.read() exceeds the limit
Keep an explicit post-read size check as a fallback
Added a regression test for oversized chunked request bodies

How to Test

Run source .venv/bin/activate
Run python -m pytest tests/gateway/test_webhook_adapter.py -q
Send a chunked webhook request larger than max_body_bytes
Confirm the adapter returns 413 instead of accepting the webhook

Notes

Manual repro before the fix: an oversized chunked request returned 202 Accepted
Manual repro after the fix: the same request returns 413 Payload too large
Full suite on current main still has unrelated failures in Slack, delegate credential resolution, transcription, website policy, and CLI tools reset tests

alt-glitch · 2026-05-02T10:12:29Z

Related to #12543 (issue) and #13336 (existing fix PR for same problem). May be duplicate of #13336.

alt-glitch · 2026-05-02T10:13:04Z

Related to #12543 (issue) and #13336 (existing fix PR for same problem). May be duplicate of #13336.

…ked-limit fix(gateway): enforce body-size limits on chunked requests (salvage #3955 + #3949)

@Gutslabs

The webhook adapter enforced max_body_bytes only via the Content-Length header; a Transfer-Encoding: chunked request (content_length=None) or a spoofed small Content-Length bypassed the cap entirely and read the full body (bounded only by aiohttp's implicit 1 MiB default, above any operator-configured smaller limit). - web.Application(client_max_size=max_body_bytes): aiohttp enforces the cap on every read path, chunked included - catch HTTPRequestEntityTooLarge -> 413 (was swallowed into generic 400) - post-read length re-check as defense in depth - chunked-upload regression test Manual port of PR NousResearch#3955 by @Gutslabs onto current main (handler had been restructured since); authorship preserved.

@Gutslabs

The webhook adapter enforced max_body_bytes only via the Content-Length header; a Transfer-Encoding: chunked request (content_length=None) or a spoofed small Content-Length bypassed the cap entirely and read the full body (bounded only by aiohttp's implicit 1 MiB default, above any operator-configured smaller limit). - web.Application(client_max_size=max_body_bytes): aiohttp enforces the cap on every read path, chunked included - catch HTTPRequestEntityTooLarge -> 413 (was swallowed into generic 400) - post-read length re-check as defense in depth - chunked-upload regression test Manual port of PR NousResearch#3955 by @Gutslabs onto current main (handler had been restructured since); authorship preserved.

…webhook-chunked-limit fix(gateway): enforce body-size limits on chunked requests (salvage NousResearch#3955 + NousResearch#3949)

teknium1 · 2026-07-12T07:54:34Z

Thanks for the security fix. This is already implemented on current main via a manual port that preserved the contribution's authorship.

Automated hermes-sweeper review verified gateway/platforms/webhook.py:216 sets client_max_size=self._max_body_bytes.
gateway/platforms/webhook.py:504-518 maps aiohttp's oversized-body exception to 413 and retains the defensive post-read size check.
tests/gateway/test_webhook_adapter.py:1164-1184 covers an oversized chunked request and confirms it is not dispatched.
Commit ec29590a0f193590e24012ff6c165de5ba2930d6 is explicitly recorded as a manual port of fix(webhook): enforce chunked body limits #3955 and is included in v2026.7.7.

@Gutslabs

The webhook adapter enforced max_body_bytes only via the Content-Length header; a Transfer-Encoding: chunked request (content_length=None) or a spoofed small Content-Length bypassed the cap entirely and read the full body (bounded only by aiohttp's implicit 1 MiB default, above any operator-configured smaller limit). - web.Application(client_max_size=max_body_bytes): aiohttp enforces the cap on every read path, chunked included - catch HTTPRequestEntityTooLarge -> 413 (was swallowed into generic 400) - post-read length re-check as defense in depth - chunked-upload regression test Manual port of PR NousResearch#3955 by @Gutslabs onto current main (handler had been restructured since); authorship preserved.

…webhook-chunked-limit fix(gateway): enforce body-size limits on chunked requests (salvage NousResearch#3955 + NousResearch#3949)

@Gutslabs

The webhook adapter enforced max_body_bytes only via the Content-Length header; a Transfer-Encoding: chunked request (content_length=None) or a spoofed small Content-Length bypassed the cap entirely and read the full body (bounded only by aiohttp's implicit 1 MiB default, above any operator-configured smaller limit). - web.Application(client_max_size=max_body_bytes): aiohttp enforces the cap on every read path, chunked included - catch HTTPRequestEntityTooLarge -> 413 (was swallowed into generic 400) - post-read length re-check as defense in depth - chunked-upload regression test Manual port of PR NousResearch#3955 by @Gutslabs onto current main (handler had been restructured since); authorship preserved.

…webhook-chunked-limit fix(gateway): enforce body-size limits on chunked requests (salvage NousResearch#3955 + NousResearch#3949)

@Gutslabs

The webhook adapter enforced max_body_bytes only via the Content-Length header; a Transfer-Encoding: chunked request (content_length=None) or a spoofed small Content-Length bypassed the cap entirely and read the full body (bounded only by aiohttp's implicit 1 MiB default, above any operator-configured smaller limit). - web.Application(client_max_size=max_body_bytes): aiohttp enforces the cap on every read path, chunked included - catch HTTPRequestEntityTooLarge -> 413 (was swallowed into generic 400) - post-read length re-check as defense in depth - chunked-upload regression test Manual port of PR NousResearch#3955 by @Gutslabs onto current main (handler had been restructured since); authorship preserved.

…webhook-chunked-limit fix(gateway): enforce body-size limits on chunked requests (salvage NousResearch#3955 + NousResearch#3949)

fix(webhook): enforce chunked body limits

8b6b751

This was referenced Apr 22, 2026

Gateway API server rejects image payloads >1MB due to missing client_max_size on aiohttp Application #13875

Closed

fix(webhook): cap chunked request bodies #13336

Closed

alt-glitch added P2 Medium — degraded but workaround exists type/security Security vulnerability or hardening comp/gateway Gateway runner, session dispatch, delivery platform/webhook Webhook / API server labels May 2, 2026

alt-glitch mentioned this pull request May 2, 2026

fix(api_server): enforce chunked request body limits #3949

Closed

3 tasks

alt-glitch mentioned this pull request Jul 2, 2026

fix(webhook): enforce body-size limit when Content-Length is absent #56829

Closed

3 tasks

teknium1 mentioned this pull request Jul 4, 2026

fix(gateway): enforce body-size limits on chunked requests (salvage #3955 + #3949) #58536

Merged

teknium1 added a commit that referenced this pull request Jul 5, 2026

Merge pull request #58536 from NousResearch/salvage/3955-webhook-chun…

f23026f

…ked-limit fix(gateway): enforce body-size limits on chunked requests (salvage #3955 + #3949)

teknium1 closed this Jul 12, 2026

teknium1 added the sweeper:implemented-on-main Sweeper: behavior already present on current main label Jul 12, 2026

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Gutslabs commented Mar 30, 2026

What does this PR do?

Type of Change

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How to Test

Notes

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alt-glitch commented May 2, 2026

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