Signature bypass via captured loop variable
Published Mar 26, 2026 · Updated Aug 26, 2026
Signature verification bypass in goxmldsig 1.5.0 and earlier allows remote attackers to submit altered XML as validly signed data. In validateSignature, the loop stores the address of the reused _ref iteration variable, so a match can resolve to the final SignedInfo reference instead. A crafted signature with multiple references can therefore substitute content from another referenced element without invalidating the signature.
Summary
What happened
Signature verification bypass in goxmldsig 1.5.0 and earlier allows remote attackers to submit altered XML as validly signed data. In validateSignature, the loop stores the address of the reused _ref iteration variable, so a match can resolve to the final SignedInfo reference instead. A crafted signature with multiple references can therefore substitute content from another referenced element without invalidating the signature.
The record
- CVE
- CVE-2026-33487
- Published
- Mar 26, 2026
- Updated
- Aug 26, 2026
- Vendor
- 389 Directory Server
- Product
- Red Hat Advanced Cluster Management for Kubernetes
- Classifications
- CWE-347, CWE-682, T1565.002
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Mar 26, 2026CVE publishedPublication date reported by the CVE source.
- Aug 26, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
- GitHub advisory proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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