Information disclosure via PKCS11 RSA heap over-read
Published May 26, 2026 · Updated Aug 31, 2026
Heap over-read in GnuTLS before 3.8.13 allows remote attackers to disclose process memory through a short RSA ClientKeyExchange. _gnutls_pkcs11_privkey_decrypt_data2 allocates a buffer using the peer-controlled ciphertext length but always reads the fixed plaintext length. Exploitation requires a server with TLS RSA or RSA-PSK enabled and a PKCS#11-backed RSA key, and the out-of-bounds read can expose adjacent heap data or crash the process.
Summary
What happened
Heap over-read in GnuTLS before 3.8.13 allows remote attackers to disclose process memory through a short RSA ClientKeyExchange. _gnutls_pkcs11_privkey_decrypt_data2 allocates a buffer using the peer-controlled ciphertext length but always reads the fixed plaintext length. Exploitation requires a server with TLS RSA or RSA-PSK enabled and a PKCS#11-backed RSA key, and the out-of-bounds read can expose adjacent heap data or crash the process.
The record
- CVE
- CVE-2026-5260
- Published
- May 26, 2026
- Updated
- Aug 31, 2026
- Vendor
- 389 Directory Server
- Product
- Red Hat OpenShift Container Platform 4.16
- Classifications
- CWE-126, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 26, 2026CVE publishedPublication date reported by the CVE source.
- Aug 31, 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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Public exploit references
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Technologies
Your stack
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Your stack
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