Description
TLS 1.3 embeds the actual record type as the last non-zero byte of the decrypted payload, optionally followed by zero padding. The code which searches for the inner record type had an off-by-one bug which could be triggered by an invalid frame, leading to an underflow followed by an unconditional NULL pointer dereference, causing a kernel panic. A remote TLS 1.3 peer can send a specially crafted record to trigger a kernel panic, resulting in a Denial of Service (DoS).
Affected products
freebsd: freebsd
References1
- security.freebsd.org/advisories/FreeBSD-SA-26:67.ktls.asc MitigationPatchVendor Advisory
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 15 · as of 10 November 2026
- CWE
- CWE-193CWE-476
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