AZL-113396: CVE-2026-97035 affecting package gcc 13.2.0-7
When using Clang or GCC, building a malicious package that uses cgo could cause unexpected code execution at build time or write files to arbitrary directories via "-gen-" or "-gnat" flags in "#cgo" directives. The "-g" wildcard in the compiler and linker flag allowlists previously matched Clang's two-argument "-gen-cdb-fragment-path <dir>" flag and GCC's two-argument "-gnatO <file>" flag, permitting compilation database fragments and sidecar output files to be written to arbitrary directories and desynchronizing flag argument parsing between the go command and the compiler driver so that subsequent arguments could be passed as unvalidated positional inputs to the linker. "-gen-" and "-gnat" flags are now disallowed in "#cgo" compiler and linker flags.
Affected Software
Event History
Frequently Asked Questions
Who is exposed to this issue?
Build environments that compile untrusted or malicious Go packages using cgo with Clang or GCC are exposed. The issue occurs during package build processing of #cgo directives.
What does an attacker need to exploit it?
An attacker needs to supply or induce a build of a malicious package containing cgo directives. The vulnerable flag allowlist could then permit compiler-driver flags that write output to arbitrary directories and cause subsequent arguments to reach the linker as unvalidated positional inputs.
Are default build configurations affected?
The provided information does not establish whether a default configuration is affected. Exploitation depends on building a package that uses cgo and contains malicious #cgo compiler or linker flags.
What mitigation is available if patching cannot happen immediately?
Avoid building untrusted cgo-enabled packages with Clang or GCC, and review package sources for #cgo compiler or linker directives using -gen-* or -gnat* flags. Restricting which packages can enter build pipelines reduces the opportunity for malicious directives to be processed.