CVE Catalog

CVE-2026-49423

Low risk· EPSS 5%
Published: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.15%

5th percentile - higher than 5% of all known CVEs

Summary

When building the iovec array for a received TLS 1.2 CBC record, ktls_ocf_tls_cbc_decrypt() incremented the iovec index for every mbuf in the chain, including mbufs that were skipped because they contained only TLS header bytes. This left uninitialized entries in the iovec array, which was allocated without zeroing. A remote TLS peer can cause the kernel to read from uninitialized iovec entries during HMAC computation, resulting in a kernel panic. The peer must be able to control TCP segmentation such that the first mbuf of a CBC record contains only the 5-byte TLS record header.

Risk Assessment

A remote attacker can cause a system crash (kernel panic), leading to service disruption and potential data loss.

Recommendation

Apply the vendor patch that ensures the iovec array is zeroed before use. Update the system to a patched version.

Original NVD description (English source)

When building the iovec array for a received TLS 1.2 CBC record, ktls_ocf_tls_cbc_decrypt() incremented the iovec index for every mbuf in the chain, including mbufs that were skipped because they contained only TLS header bytes. This left uninitialized entries in the iovec array. The iovec array was allocated without zeroing. A remote TLS peer can cause the kernel to read from uninitialized iovec entries during HMAC computation, resulting in a kernel panic. The peer must be able to control TCP segmentation such that the first mbuf of a CBC record contains only the 5-byte TLS record header.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS