XML signature forgery via noncanonical reference validation
Published Nov 30, 2023 · Updated Aug 2, 2024
Improper signature verification in SimpleSAMLphp xml-security 1.6.11 and 5.0.0-alpha.12 allows remote attackers to forge XML signatures. SignedElementTrait::verifyInternal verifies canonicalized SignedInfo bytes, but validateReference reads references from the original noncanonical tree. Exploitation requires a PHP canonicalization discrepancy that changes DigestValue; the advisory reports no working trigger, and the bounded consequence is acceptance of forged signed XML.
Summary
What happened
Improper signature verification in SimpleSAMLphp xml-security 1.6.11 and 5.0.0-alpha.12 allows remote attackers to forge XML signatures. SignedElementTrait::verifyInternal verifies canonicalized SignedInfo bytes, but validateReference reads references from the original noncanonical tree. Exploitation requires a PHP canonicalization discrepancy that changes DigestValue; the advisory reports no working trigger, and the bounded consequence is acceptance of forged signed XML.
The record
- CVE
- CVE-2023-49087
- Published
- Nov 30, 2023
- Updated
- Aug 2, 2024
- Vendor
- SimpleSAMLphp
- Product
- xml-security
- Classifications
- CWE-345, T1606.002
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Nov 30, 2023CVE publishedPublication date reported by the CVE source.
- Aug 2, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion== 1.6.11
- Affected versionversion== 5.0.0-alpha.12
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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