Improper Validation of Syntactic Correctness of Input Affecting github.com/andybalholm/brotli package, versions <1.2.7
Threat Intelligence
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Snyk has reported that there have been attempts or successful attacks targeting this vulnerability.
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Test your applications- Snyk IDSNYK-GOLANG-GITHUBCOMANDYBALHOLMBROTLI-22221607
- published5 Nov 2026
- disclosed21 Oct 2026
- creditUnknown
Introduced: 21 Oct 2026
NewCVE-2026-111497 (opens in a new tab)How to fix?
Upgrade github.com/andybalholm/brotli to version 1.2.7 or higher.
Overview
Affected versions of this package are vulnerable to Improper Validation of Syntactic Correctness of Input via the decodeBlockTypeAndLength function in the Brotli decoder. An attacker can crash the process or cause an indefinite decoding loop by supplying malformed Brotli-compressed data with an invalid block-switch command, which causes the decoder to read past the end of the input. The issue affects applications that decode attacker-controlled compressed data.
Notes
- According to the maintainer, the Go implementation is only vulnerable to denial of service, instead of a buffer overflow or RCE