Description
In the Linux kernel, the following vulnerability has been resolved: udf: reject descriptors with oversized CRC length udf_read_tagged() skips CRC verification when descCRCLength + sizeof(struct tag) exceeds the block size. A crafted UDF image can set descCRCLength to an oversized value to bypass CRC validation entirely; the descriptor is then accepted based solely on the 8-bit tag checksum, which is trivially recomputable. Reject such descriptors instead of silently accepting them. A legitimate single-block descriptor should never have a CRC length that exceeds the block.
Affected products
linux: linux kernel
References8
- git.kernel.org/stable/c/1873eb81c65d3f849418d7386baa39c439c9fc38 Patch
- git.kernel.org/stable/c/31605bbe94557bff721eaf041001169d44ac6f98 Patch
- git.kernel.org/stable/c/3dede76d525919bb966f9213e131af685de5ff99 Patch
- git.kernel.org/stable/c/50dfaf4a027742b4fcdc3e9305e7199ece9bc6a6 Patch
- git.kernel.org/stable/c/55d41b0a20128e86b9e960dd2e3f0a2d69a18df7 Patch
- git.kernel.org/stable/c/7d1b6adbf90df6c8941090d5646fbeca25ba9770 Patch
- git.kernel.org/stable/c/832ab4a882dc9b3c0155490d9993642ef545fd22 Patch
- git.kernel.org/stable/c/fdb26e628d2a211a23815d375bd33bdf863344e2 Patch
Metrics
- CVSS 3.1
-
8.4
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 9 · as of 14 November 2026
- CWE
- CWE-20
Could this be exploited in your environment?
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