CVE-2026-27140 Code execution vulnerability in SWIG code generation in cmd/go
High 8.8
Published
Updated
Check this codebase for CVE-2026-27140 and fix it if it is affected.
What it is: CVE-2026-27140 is a high-severity code injection vulnerability in Golang Go, published on 8 Apr 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-27140 in the wild and no public exploit code.
Affected packages and fixed versions:
- golang (Bitnami): affected all versions; fixed in 1.25.9, 1.26.2
- toolchain (Go): affected all versions; fixed in 1.25.9, 1.26.2
Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.
Reference: https://insights.sbomify.com/CVE-2026-27140/ (Markdown: https://insights.sbomify.com/CVE-2026-27140/index.md)
Attackers can execute arbitrary code during build time by crafting SWIG filenames that bypass trust layers in the Go toolchain.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-27140?
CVE-2026-27140 is a high-severity code injection vulnerability in Golang Go, published on 8 Apr 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
SWIG file names containing 'cgo' and well-crafted payloads could lead to code smuggling and arbitrary code execution at build time due to trust layer bypass.
Which versions are affected by CVE-2026-27140?
2 open source packages ship an affected version, including golang and toolchain. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
golang Bitnami | All versions | 1.25.9, 1.26.2 |
toolchain Go | All versions | 1.25.9, 1.26.2 |
Linux distribution packages (38)
delve Red Hat:rhel_aus:8.4::appstream | All versions | 0:1.5.0-2.module+el8.4.0+8864+58b0fcdb |
delve-debuginfo Red Hat:rhel_aus:8.4::appstream | All versions | 0:1.5.0-2.module+el8.4.0+8864+58b0fcdb |
delve-debugsource Red Hat:rhel_aus:8.4::appstream | All versions | 0:1.5.0-2.module+el8.4.0+8864+58b0fcdb |
go-toolset Red Hat:rhel_aus:8.4::appstream | All versions | 0:1.15.14-3.module+el8.4.0+22765+91da4d3f |
golang Red Hat:rhel_aus:8.4::appstream | All versions | 0:1.15.14-22.module+el8.4.0+24267+d2faeddf |
golang-bin Red Hat:rhel_aus:8.4::appstream | All versions | 0:1.15.14-22.module+el8.4.0+24267+d2faeddf |
golang-docs Red Hat:rhel_aus:8.4::appstream | All versions | 0:1.15.14-22.module+el8.4.0+24267+d2faeddf |
golang-misc Red Hat:rhel_aus:8.4::appstream | All versions | 0:1.15.14-22.module+el8.4.0+24267+d2faeddf |
golang-race Red Hat:rhel_aus:8.4::appstream | All versions | 0:1.15.14-22.module+el8.4.0+24267+d2faeddf |
golang-src Red Hat:rhel_aus:8.4::appstream | All versions | 0:1.15.14-22.module+el8.4.0+24267+d2faeddf |
golang-tests Red Hat:rhel_aus:8.4::appstream | All versions | 0:1.15.14-22.module+el8.4.0+24267+d2faeddf |
delve Red Hat:rhel_aus:8.6::appstream | All versions | 0:1.7.2-1.module+el8.6.0+12972+ebab5911 |
delve-debuginfo Red Hat:rhel_aus:8.6::appstream | All versions | 0:1.7.2-1.module+el8.6.0+12972+ebab5911 |
delve-debugsource Red Hat:rhel_aus:8.6::appstream | All versions | 0:1.7.2-1.module+el8.6.0+12972+ebab5911 |
go-toolset Red Hat:rhel_aus:8.6::appstream | All versions | 0:1.17.13-2.module+el8.6.0+22782+bd95fb4c |
golang Red Hat:rhel_aus:8.6::appstream | All versions | 0:1.17.13-16.module+el8.6.0+24266+ace38400 |
golang-bin Red Hat:rhel_aus:8.6::appstream | All versions | 0:1.17.13-16.module+el8.6.0+24266+ace38400 |
golang-docs Red Hat:rhel_aus:8.6::appstream | All versions | 0:1.17.13-16.module+el8.6.0+24266+ace38400 |
golang-misc Red Hat:rhel_aus:8.6::appstream | All versions | 0:1.17.13-16.module+el8.6.0+24266+ace38400 |
golang-race Red Hat:rhel_aus:8.6::appstream | All versions | 0:1.17.13-16.module+el8.6.0+24266+ace38400 |
golang-src Red Hat:rhel_aus:8.6::appstream | All versions | 0:1.17.13-16.module+el8.6.0+24266+ace38400 |
golang-tests Red Hat:rhel_aus:8.6::appstream | All versions | 0:1.17.13-16.module+el8.6.0+24266+ace38400 |
delve Red Hat:rhel_e4s:8.6::appstream | All versions | 0:1.7.2-1.module+el8.6.0+12972+ebab5911 |
delve-debuginfo Red Hat:rhel_e4s:8.6::appstream | All versions | 0:1.7.2-1.module+el8.6.0+12972+ebab5911 |
delve-debugsource Red Hat:rhel_e4s:8.6::appstream | All versions | 0:1.7.2-1.module+el8.6.0+12972+ebab5911 |
go-toolset Red Hat:rhel_e4s:8.6::appstream | All versions | 0:1.17.13-2.module+el8.6.0+22782+bd95fb4c |
golang Red Hat:rhel_e4s:8.6::appstream | All versions | 0:1.17.13-16.module+el8.6.0+24266+ace38400 |
golang-bin Red Hat:rhel_e4s:8.6::appstream | All versions | 0:1.17.13-16.module+el8.6.0+24266+ace38400 |
golang-docs Red Hat:rhel_e4s:8.6::appstream | All versions | 0:1.17.13-16.module+el8.6.0+24266+ace38400 |
golang-misc Red Hat:rhel_e4s:8.6::appstream | All versions | 0:1.17.13-16.module+el8.6.0+24266+ace38400 |
golang-race Red Hat:rhel_e4s:8.6::appstream | All versions | 0:1.17.13-16.module+el8.6.0+24266+ace38400 |
golang-src Red Hat:rhel_e4s:8.6::appstream | All versions | 0:1.17.13-16.module+el8.6.0+24266+ace38400 |
golang-tests Red Hat:rhel_e4s:8.6::appstream | All versions | 0:1.17.13-16.module+el8.6.0+24266+ace38400 |
delve Red Hat:rhel_e4s:8.8::appstream | All versions | 0:1.9.1-1.module+el8.8.0+16778+5fbb74f5 |
delve-debuginfo Red Hat:rhel_e4s:8.8::appstream | All versions | 0:1.9.1-1.module+el8.8.0+16778+5fbb74f5 |
delve-debugsource Red Hat:rhel_e4s:8.8::appstream | All versions | 0:1.9.1-1.module+el8.8.0+16778+5fbb74f5 |
go-toolset Red Hat:rhel_e4s:8.8::appstream | All versions | 0:1.19.13-4.module+el8.8.0+23976+18ba1869 |
golang Red Hat:rhel_e4s:8.8::appstream | All versions | 0:1.19.13-24.module+el8.8.0+24268+9f9e0e19 |
Products include Golang Go.
How do I fix CVE-2026-27140?
Upgrade golang to a fixed version for your release line: 1.25.9 or 1.26.2.
Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.
Is CVE-2026-27140 being exploited?
There is no known exploitation of CVE-2026-27140 in the wild and no public exploit code.
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- CVE-2023-39320 Arbitrary code execution via go.mod toolchain directive in cmd/go
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Sources
Also known as AZL-98607, BELL-CVE-2026-27140, BIT-golang-2026-27140, CLEANSTART-2026-GQ35594, CLEANSTART-2026-KD34055, CLEANSTART-2026-OK73778 and 648 more.