Memory corruption via unchecked signed-message length
Published May 8, 2026 · Updated May 8, 2026
Buffer overflow in crypto_sign_open() in CROSS implementation before commit fc6b7e7 allows attackers to corrupt memory via an undersized signed message. The function subtracts sizeof(CROSS_sig_t) from attacker-controlled smlen without first checking its minimum size, causing unsigned mlen to wrap before subsequent memory operations. Exploitation requires a consuming binary to pass a signed-message buffer shorter than one CROSS signature, and consequences remain within that binary's process.
Summary
What happened
Buffer overflow in crypto_sign_open() in CROSS implementation before commit fc6b7e7 allows attackers to corrupt memory via an undersized signed message. The function subtracts sizeof(CROSS_sig_t) from attacker-controlled smlen without first checking its minimum size, causing unsigned mlen to wrap before subsequent memory operations. Exploitation requires a consuming binary to pass a signed-message buffer shorter than one CROSS signature, and consequences remain within that binary's process.
The record
- CVE
- CVE-2026-41509
- Published
- May 8, 2026
- Updated
- May 8, 2026
- Vendor
- CROSS Signature team
- Product
- CROSS implementation
- Classifications
- CWE-121, CWE-122
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 8, 2026CVE publishedPublication date reported by the CVE source.
- May 8, 2026Record updatedLatest update available in the CVE record.
Exploitability
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- Affected versionversion=< fc6b7e78cdf789bb5c395a81dc601356f1383da0
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Technologies
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Your stack
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