CVE-2026-97042 Linker flag injection via cgo_import_dynamic and PE DLL names in cmd/cgo, cmd/compile, and cmd/link
- Exploited in the wild
- Not known
- Fix
- Available
What is CVE-2026-97042?
CVE-2026-97042 is a vulnerability in cmd/cgo, published on 11 Nov 2026.
Official description
Building a malicious package that uses "//go:cgo_import_dynamic" or links against a crafted PE object on Windows could pass unsafe library arguments to the external linker. The compiler only checked the first character of the library name in "//go:cgo_import_dynamic" directives and skipped validation in cgo-generated files. In addition, on Windows, "cmd/cgo" and "cmd/link" did not validate imported DLL names extracted from PE object files before emitting "-l<name>" flags for the external linker, allowing a crafted DLL name containing ".." path traversal or special characters to reference arbitrary files on disk. The compiler now validates every character of the library name in "//go:cgo_import_dynamic" directives (including in cgo-generated files on Windows) and rejects ".." path traversal, and "cmd/cgo" and "cmd/link" reject PE imported DLL names containing path separators, "..", ":", or leading "-" or "@".
Which versions are affected by CVE-2026-97042?
1 open source package ship an affected version, including toolchain.
| Package | Affected | Fixed in |
|---|---|---|
toolchain Go | All versions | 1.26.11, 1.27.4 |
How do I fix CVE-2026-97042?
Upgrade toolchain to a fixed version for your release line: 1.26.11 or 1.27.4.
Is CVE-2026-97042 being exploited?
There is no known exploitation of CVE-2026-97042 in the wild and no public exploit code.
Sources
Also known as ALPINE-CVE-2026-97042, DEBIAN-CVE-2026-97042, GHSA-jgj7-3254-vwmv, GO-2026-6849, UBUNTU-CVE-2026-97042.