CVE-2026-33487
goxmlsig provides XML Digital Signatures implemented in Go.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.30%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
goxmlsig provides XML Digital Signatures implemented in Go. Prior to version 1.6.0, the `validateSignature` function in `validate.go` goes through the references in the `SignedInfo` block to find one that matches the signed element's ID. In Go versions before 1.22, or when `go.mod` uses an older version, there is a loop variable capture issue. The code takes the address of the loop variable `_ref` instead of its value. As a result, if more than one reference matches the ID or if the loop logic is incorrect, the `ref` pointer will always end up pointing to the last element in the `SignedInfo.References` slice after the loop. goxmlsig version 1.6.0 contains a patch.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
- EPSS
- 0.30% probability · 22th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-347, CWE-682
- Affected
- goxmldsig project/goxmldsig
- Source
- security-advisories@github.com
References
- https://github.com/russellhaering/goxmldsig/security/advisories/GHSA-479m-364c-43vcExploit, Mitigation, Vendor Advisory
- https://access.redhat.com/errata/RHSA-2026:13548
- https://access.redhat.com/errata/RHSA-2026:20943
- https://access.redhat.com/errata/RHSA-2026:20946
- https://access.redhat.com/errata/RHSA-2026:21769
- https://access.redhat.com/errata/RHSA-2026:22347
- https://access.redhat.com/errata/RHSA-2026:22423
- https://access.redhat.com/errata/RHSA-2026:23345
- https://access.redhat.com/errata/RHSA-2026:36882
- https://access.redhat.com/security/cve/CVE-2026-33487
- https://bugzilla.redhat.com/show_bug.cgi?id=2451814
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33487.json
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.