CVE-2025-40049
What it is
In the Linux kernel, the following vulnerability has been resolved: Squashfs: fix uninit-value in squashfs_get_parent Syzkaller reports a "KMSAN: uninit-value in squashfs_get_parent" bug. This is caused by open_by_handle_at() being called with a file handle containing an invalid parent inode number. In particular the inode number is that of a symbolic link, rather than a directory. Squashfs_get_parent() gets called with that symbolic link inode, and accesses the parent member field. unsigned int parent_ino = squashfs_i(inode)->parent; Because non-directory inodes in Squashfs do not have a parent value, this is uninitialised, and this causes an uninitialised value access. The fix is to initialise parent with the invalid inode 0, which will cause an EINVAL error to be returned. Regular inodes used to share the parent field with the block_list_start field. This is removed in this commit to enable the parent field to contain the invalid inode number 0.
At a glance
- Exploit odds
- 0.2% chance of exploitation in the next 30 days (EPSS).
- Fix
- No patch or advisory is linked yet. Look at mitigations or restrict exposure.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.2% in the next 30 days (EPSS).
- Severity: not scored yet.
- Fix: none linked yet, which raises it.
Details
- Published
- Last modified
- Exploit probability
- 0.2% · EPSS, next 30 days
- Record status
- Deferred
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2025-40049.md and follow it. Check whether this project is affected by CVE-2025-40049. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
References
- https://git.kernel.org/stable/c/1b3ccd0019132880c94bb00ca7088c1749308f82
- https://git.kernel.org/stable/c/382a47fae449e554ef1e8c198667fd2f3270b945
- https://git.kernel.org/stable/c/61d38b5ce2782bff3cacaacbb8164087a73ed1a5
- https://git.kernel.org/stable/c/74058c0a9fc8b2b4d5f4a0ef7ee2cfa66a9e49cf
- https://git.kernel.org/stable/c/81a2bca52d43fc9d9abf07408b91255131c5dc53
- https://git.kernel.org/stable/c/91b99db7a92e57ff48a96a1b10fddfd2547e7f53
- https://git.kernel.org/stable/c/c28b0ca029edf5d0558abcd76cb8c732706cd339
- https://git.kernel.org/stable/c/f81a5bc9e924ee1950e0dd82bd10749048390f6e