CVE-2026-97043 Unexpected code execution via escaped quotes in //go:cgo_ldflag in cmd/go and cmd/compile
- Exploited in the wild
- Not known
- Fix
- Available
What is CVE-2026-97043?
CVE-2026-97043 is a vulnerability in Go toolchain cmd/compile, published on 11 Nov 2026.
Official description
Building a malicious package that uses cgo could bypass "#cgo LDFLAGS" validation and cause unexpected code execution at build time, or cause the go command to panic, via crafted quoting in "//go:cgo_ldflag" directives. When "cmd/cgo" generates "_cgo_gotypes.go", it quotes each "#cgo LDFLAGS" argument with strconv.Quote in a "//go:cgo_ldflag" directive, but "cmd/compile" and "cmd/go" parsed those directives by splitting on raw quote characters without handling backslash escapes or unquoting the string. This mismatch allowed disallowed linker flags or unvalidated linker search paths to be smuggled past the go command's flag checks and passed to the external linker. In addition, deduplicating LDFLAGS in the go command could panic with an out-of-bounds slice index when a prefix of the flag list matched near the end of the slice. "cmd/compile" and "cmd/go" now properly handle backslash-escaped quotes and unquote "//go:cgo_*" pragma strings with strconv.Unquote, and the slice bounds check in processCgoOutputs has been fixed.
Which versions are affected by CVE-2026-97043?
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-2026-97043?
Upgrade toolchain to a fixed version for your release line: 1.26.11 or 1.27.4.
Is CVE-2026-97043 being exploited?
There is no known exploitation of CVE-2026-97043 in the wild and no public exploit code.
Sources
Also known as ALPINE-CVE-2026-97043, DEBIAN-CVE-2026-97043, GHSA-26gx-chjm-8pq7, GO-2026-6848, UBUNTU-CVE-2026-97043.