CVE-2026-27140: Go toolchain cmd/go · Trust Boundary Violation
Affects Go toolchain cmd/goSource CVE Database V5
Not known to be exploited · CVSS 8.8 High : upgrade to 1.26.2 or 1.25.9 soon.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.6% chance of exploitation in 30 days – higher than 51% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 1.26.2, 1.25.9
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 8 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade Go toolchain cmd/go to 1.26.2 or 1.25.9.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Go toolchaincmd/go | Affected
| Fixed in
|
| Go toolchaincmd/go | Affected
| Fixed in
|
Gocmd/gopkg:golang/cmd/goOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Red Hat has released security updates for golang packages that address CVE-2026-27140. Users should apply these official patches as provided in the referenced Red Hat advisories (e.g., RHSA-2026:16024 and others). Since this is a vulnerability in the build toolchain, updating to the fixed golang package version is the recommended remediation. Patch status is not explicitly stated in the input but the presence of multiple Red Hat errata indicates that fixes are available. Check the vendor advisories for detailed update instructions and apply them promptly.
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.
References
- go.dev/cl/763768 (opens in a new tab)
- go.dev/issue/78335 (opens in a new tab)
- groups.google.com/g/golang-announce/c/0uYbvbPZRWU (opens in a new tab)
- pkg.go.dev/vuln/GO-2026-4871 (opens in a new tab)
- access.redhat.com/security/cve/CVE-2026-27140 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2456341 (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-27140.json (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:16024 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:10217 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:10704 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:16698 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:16697 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:16694 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:16494 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:16498 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:16497 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:16021 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:10219 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:34099 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:25182 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:23246 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:57545 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:56854 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:57408 (opens in a new tab)