Description
In the Linux kernel, the following vulnerability has been resolved: caif: fix integer underflow in cffrml_receive() The cffrml_receive() function extracts a length field from the packet header and, when FCS is disabled, subtracts 2 from this length without validating that len >= 2. If an attacker sends a malicious packet with a length field of 0 or 1 to an interface with FCS disabled, the subtraction causes an integer underflow. This can lead to memory exhaustion and kernel instability, potential information disclosure if padding contains uninitialized kernel memory. Fix this by validating that len >= 2 before performing the subtraction.
References7
- git.kernel.org/stable/c/21fdcc00656a60af3c7aae2dea8dd96abd35519c
- git.kernel.org/stable/c/4ec29714aa4e0601ea29d2f02b461fc0ac92c2c3
- git.kernel.org/stable/c/785c7be6361630070790f6235b696da156ac71b3
- git.kernel.org/stable/c/8a11ff0948b5ad09b71896b7ccc850625f9878d1
- git.kernel.org/stable/c/c54091eec6fed19e94182aa05dd6846600a642f7
- git.kernel.org/stable/c/f407f1c9f45bbf5c99fd80b3f3f4a94fdbe35691
- git.kernel.org/stable/c/f818cd472565f8b0c2c409b040e0121c5cf8592c
Metrics
- CVSS 3.1
-
8.1
HIGH
Score source: CNA
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H - EPSS — exploit probability
- 0% percentile: 24 · as of 12 November 2026
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