Compress/s2: Integer Overflow or Wraparound and Out-of-bounds Write in compress

Date Oct 20, 2026
Type Vendor advisory
Signal High-risk advisory
Vendor / Product Go ยท github.com/klauspost/compress
CVE CVE-2026-63209
High-risk advisory CVE-2026-63209

Summary

Compress/s2: Integer Overflow or Wraparound and Out-of-bounds Write in compress

Why it matters

GitHub has published a reviewed security advisory for github.com/klauspost/compress. Prioritize it with other application dependency updates, especially because EPSS places it in the 29% percentile.

Operator check

Check whether github.com/klauspost/compress is present in application dependency manifests, lockfiles, or build images. Review the GitHub advisory and upgrade to a patched version where available. EPSS probability: 0.4%; percentile: 29%.

Sources

PatchBrief uses public sources. It does not scan environments, verify exposure, or replace vendor guidance.