Arbitrary code execution via crafted .syso files and cgo linker input files in cmd/go

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

not scored

EPSS

No dated EPSS signal available.

As published by the source; long descriptions are shortened.

Building a malicious package containing ".syso" files or cgo linker inputs could inject arbitrary linker flags or execute arbitrary code at link time. Linker input files—including ".syso" files, direct object or library inputs in "#cgo LDFLAGS", and libraries in "-L" directories—were passed to the external linker without validating their format or checking for embedded linker options. Across platforms, this allowed executing GNU ld implicit linker scripts disguised as libraries or ".syso" files (or loaded via "-l: " or "-l" containing path separators), injecting unallowlisted linker flags via PE/COFF ".drectve" sections on Windows or Mach-O "LC_LINKER_OPTION" load commands on Darwin, or invoking LTO plugins via GCC or LLVM LTO intermediate representation sections in ELF, PE/COFF, or Mach-O objects. The go command now verifies that ".syso" files, direct linker inputs, and libraries in "-L" directories are valid binary objects or archives that do not contain unallowlisted ".drectve"…

Published by the source

11 Nov 2026, 02:51 UTC

Last modified by the source

11 Nov 2026, 03:15 UTC

Source last checked

11 Nov 2026, 07:20 UTC

1. Revision 1 · created · 11 Nov 2026

   Published from osv record GO-2026-6853

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# Patch Next advisory brief: CVE-2026-97038

Advisory: Arbitrary code execution via crafted .syso files and cgo linker input files in cmd/go
IDs: CVE-2026-97038
Record: https://patchnext.com/advisories/cve-2026-97038 (revision 1, source checked 11 Nov 2026, 07:20 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Unrated
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: toolchain 1.27.4, 1.26.11. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go toolchain: affected < 1.26.11; >= 1.27.0-0, < 1.27.4; fixed in 1.26.11, 1.27.4

## Suggested inspection (read-only)
- Go toolchain: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on toolchain.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GO-2026-6853 (OSV record GO-2026-6853 lists affected ranges: Go toolchain >=0 =1.27.0-0 <1.27.4 (fixed))

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