Description
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.
Published: 2026-08-19
Score: n/a
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

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Remediation

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History

Wed, 19 Aug 2026 11:45:00 +0000

Type Values Removed Values Added
First Time appeared Freebsd
Freebsd freebsd
Vendors & Products Freebsd
Freebsd freebsd

Wed, 19 Aug 2026 07:15:00 +0000

Type Values Removed Values Added
Description 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.
Title Remote DOS via uninitialized memory access in KTLS receive
Weaknesses CWE-908
References

cve-icon MITRE

Status: PUBLISHED

Assigner: freebsd

Published:

Updated: 2026-08-19T07:01:49.801Z

Reserved: 2026-05-29T20:24:28.616Z

Link: CVE-2026-49423

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-08-19T07:16:28.570

Modified: 2026-08-19T07:16:28.570

Link: CVE-2026-49423

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-19T11:30:04Z

Weaknesses
  • CWE-908

    Use of Uninitialized Resource