CVE-2026-33487 — goxmldsig has validateSignature Loop Variable Capture Signature Bypass

Description (CNA)

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.

Affected (CNA)

Vendor / product	Versions
russellhaering / goxmldsig	affected < 1.6.0

CWE

CWE-347, CWE-682

References

https://github.com/russellhaering/goxmldsig/security/advisories/GHSA-479m-364c-43vc

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.

redhat-SADP

A flaw was found in goxmlsig, a Go library for XML Digital Signatures. This vulnerability arises from a programming error, specifically a loop variable capture issue, within the `validateSignature` function. When processing XML Digital Signatures, this error can cause the system to incorrectly validate the signature, potentially allowing an attacker to bypass integrity checks. This issue affects Go versions before 1.22 or projects using older `go.mod` configurations.