Out-of-bounds Write Affecting node package, versions [22.0.0, 22.23.4)[24.0.0, 24.22.1)[26.0.0, 26.12.1)


Severity

Recommended
0.0
critical
0
10

CVSS assessment by Snyk's Security Team. Learn more

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  • Snyk IDSNYK-UPSTREAM-NODE-21427911
  • published22 Oct 2026
  • disclosed21 Oct 2026
  • creditmcollina

Introduced: 21 Oct 2026

NewCVE-2026-111497  (opens in a new tab)
CWE-787  (opens in a new tab)

How to fix?

Upgrade node to version 22.23.4, 24.22.1, 26.12.1 or higher.

Overview

node is a JavaScript runtime built on Chrome's V8 JavaScript engine.

Affected versions of this package are vulnerable to Out-of-bounds Write via block-switch handling in the Brotli decoder, specifically DecodeBlockTypeAndLength in deps/brotli/c/dec/decode.c. An attacker can execute arbitrary code by supplying a crafted Brotli-compressed stream with an invalid block switch to Node.js code that decodes it; the decoder fails to propagate the block-switch error during command processing, allowing the out-of-bounds write.

Notes

  • At a literal, command, or distance block-switch, the vulnerable path is reached when that stream’s block-type count is at most one (max_block_type <= 1); the decoder’s boolean failure is then discarded by the unsafe switch path, which continues processing.

CVSS Base Scores

version 4.0
version 3.1