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no cvss —

CVE-2026-97034 json

Arbitrary command execution via GCC spec files in cgo linker search directories in cmd/go

published yesterday modified yesterday also EUVD-2026-123111 , GO-2026-6857

cvss
—
not scored
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 20%
public exploits
0
none known

Summary

When using GCC, building a malicious package that uses cgo could cause arbitrary command execution at link time via untrusted GCC spec files ("specs" or "*.spec"). When linking with "-fopenmp", "-fopenacc", or "-fsanitize=" in "#cgo LDFLAGS", GCC's built-in link spec evaluates "%:include(libgomp.spec)" or "%:include(libsanitizer.spec)" and searches for spec files in "-L" and sysroot directories (including subdirectories and multilib sibling directories such as "../lib64"), as well as the working directory when "-fopenmp" or "-fopenacc" is used or when "-fsanitize=" is combined with "-static" or "-static-lib*". The go command now rejects "-L", "-isysroot", and "-Wl,-syslibroot" directories (and the working and package directories when applicable) that contain GCC spec files, and disallows "@" and "-" prefixes in "-fsanitize=" compiler flag values.

Patch / fix

  • go toolchain 1.26.11, 1.27.4
  • Go toolchain cmd/go 1.26.11, 1.27.4

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Exploit prediction

0.28% chance of exploitation in the next 30 days, higher than 20% of all scored CVEs (FIRST EPSS, 2026-11-11).

Affected packages

ecosystem package affected fixed in
go toolchain
<1.26.11
>=1.27.0-0, <1.27.4
1.26.11
1.27.4

Affected products

  • Go toolchain cmd/go

Classification

Weakness
  • CWE-77 Improper Neutralization of Special Elements used in a Command

References

Sources

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