AZL-113588: CVE-2026-97035 affecting package python-tensorboard 2.16.2-6
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 using Clang or GCC are exposed when they build a malicious package that contains cgo directives. The issue occurs during package build time.
What does an attacker need to exploit it?
An attacker needs to provide a malicious package using cgo with crafted #cgo compiler or linker flags. The affected flags are the previously allowlisted -gen-* and -gnat* patterns.
What can happen if exploitation succeeds?
A malicious build can cause unexpected code execution at build time or write compilation database fragments and sidecar output files to arbitrary directories. It may also cause later arguments to be passed to the linker as unvalidated positional inputs.
What mitigation is described?
Disallow -gen-* and -gnat* flags in #cgo compiler and linker flags. This prevents the two-argument Clang -gen-cdb-fragment-path and GCC -gnatO flag cases described.