cbcvebase.
CVE-2025-40049
published 2025-10-28

CVE-2025-40049: In the Linux kernel, the following vulnerability has been resolved: Squashfs: fix uninit-value in squashfs_get_parent Syzkaller reports a "KMSAN: uninit-value…

PriorityP420high7.8
EPSS
0.21%
11.6th percentile
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.

Affected

32 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.158-1 (bookworm)linux 6.1.158-1 (bookworm)
debianlinux-6.1< linux 6.1.158-1 (bookworm)linux 6.1.158-1 (bookworm)
linuxlinux
linuxlinux>= 122601408d20c77704268f1dea9f9ce4abf997c2 < f81a5bc9e924ee1950e0dd82bd10749048390f6ef81a5bc9e924ee1950e0dd82bd10749048390f6e
linuxlinux>= 122601408d20c77704268f1dea9f9ce4abf997c2 < 382a47fae449e554ef1e8c198667fd2f3270b945382a47fae449e554ef1e8c198667fd2f3270b945
linuxlinux>= 122601408d20c77704268f1dea9f9ce4abf997c2 < 61d38b5ce2782bff3cacaacbb8164087a73ed1a561d38b5ce2782bff3cacaacbb8164087a73ed1a5
linuxlinux>= 122601408d20c77704268f1dea9f9ce4abf997c2 < 81a2bca52d43fc9d9abf07408b91255131c5dc5381a2bca52d43fc9d9abf07408b91255131c5dc53
linuxlinux>= 122601408d20c77704268f1dea9f9ce4abf997c2 < c28b0ca029edf5d0558abcd76cb8c732706cd339c28b0ca029edf5d0558abcd76cb8c732706cd339
linuxlinux>= 122601408d20c77704268f1dea9f9ce4abf997c2 < 1b3ccd0019132880c94bb00ca7088c1749308f821b3ccd0019132880c94bb00ca7088c1749308f82
linuxlinux>= 122601408d20c77704268f1dea9f9ce4abf997c2 < 91b99db7a92e57ff48a96a1b10fddfd2547e7f5391b99db7a92e57ff48a96a1b10fddfd2547e7f53
linuxlinux>= 122601408d20c77704268f1dea9f9ce4abf997c2 < 74058c0a9fc8b2b4d5f4a0ef7ee2cfa66a9e49cf74058c0a9fc8b2b4d5f4a0ef7ee2cfa66a9e49cf
linuxlinux_kernel>= 0 < 5.10.247-15.10.247-1
linuxlinux_kernel>= 0 < 6.1.158-16.1.158-1
linuxlinux_kernel>= 0 < 6.12.57-16.12.57-1
linuxlinux_kernel>= 0 < 6.17.6-16.17.6-1
linuxlinux_kernel>= 0 < 5.15.0-170.1805.15.0-170.180
linuxlinux_kernel>= 0 < 6.8.0-106.1066.8.0-106.106
linuxlinux_kernel>= 0 < 6.17.0-14.146.17.0-14.14
linuxlinux_kernel>= 2.6.29 < 5.4.3015.4.301
linuxlinux_kernel>= 5.11.0 < 5.15.1955.15.195
linuxlinux_kernel>= 5.16.0 < 6.1.1566.1.156
linuxlinux_kernel>= 5.5.0 < 5.10.2465.10.246
linuxlinux_kernel>= 6.13.0 < 6.17.36.17.3
linuxlinux_kernel>= 6.2.0 < 6.6.1126.6.112
linuxlinux_kernel>= 6.7.0 < 6.12.536.12.53

CVSS provenance

osv7.8HIGH
vendor_ubuntu7.8HIGH
vendor_msrc5.5MEDIUM
vendor_redhat5.5LOW
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