cbcvebase.
CVE-2025-68299
published 2025-12-16

CVE-2025-68299: In the Linux kernel, the following vulnerability has been resolved: afs: Fix delayed allocation of a cell's anonymous key The allocation of a cell's anonymous…

PriorityP423high7.2
EPSS
0.24%
15.4th percentile
In the Linux kernel, the following vulnerability has been resolved: afs: Fix delayed allocation of a cell's anonymous key The allocation of a cell's anonymous key is done in a background thread along with other cell setup such as doing a DNS upcall. In the reported bug, this is triggered by afs_parse_source() parsing the device name given to mount() and calling afs_lookup_cell() with the name of the cell. The normal key lookup then tries to use the key description on the anonymous authentication key as the reference for request_key() - but it may not yet be set and so an oops can happen. This has been made more likely to happen by the fix for dynamic lookup failure. Fix this by firstly allocating a reference name and attaching it to the afs_cell record when the record is created. It can share the memory allocation with the cell name (unfortunately it can't just overlap the cell name by prepending it with "afs@" as the cell name already has a '.' prepended for other purposes). This reference name is then passed to request_key(). Secondly, the anon key is now allocated on demand at the point a key is requested in afs_request_key() if it is not already allocated. A mutex is used to prevent multiple allocation for a cell. Thirdly, make afs_request_key_rcu() return NULL if the anonymous key isn't yet allocated (if we need it) and then the caller can return -ECHILD to drop out of RCU-mode and afs_request_key() can be called. Note that the anonymous key is kind of necessary to make the key lookup cache work as that doesn't currently cache a negative lookup, but it's probably worth some investigation to see if NULL can be used instead.

Affected

8 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.17.11-1 (forky)linux 6.17.11-1 (forky)
linuxlinux>= 330e2c514823008b22e6afd2055715bc46dd8d55 < d27c71257825dced46104eefe42e4d9964bd032ed27c71257825dced46104eefe42e4d9964bd032e
linuxlinux>= 6.17.9 < 6.17.116.17.11
linuxlinux>= 7e33b15d5a6578a99ebf189cea34983270ae92dd < 5613bde937dfac6725e9c3fc766b9d6b8481e55b5613bde937dfac6725e9c3fc766b9d6b8481e55b
linuxlinux>= fa4ccdccf1489a6dac4369a8c69f11b455b3355c < bd18d2cbc9377c6b270c0b7ea44b0e6ed1d99c07bd18d2cbc9377c6b270c0b7ea44b0e6ed1d99c07
linuxlinux_kernel>= 0 < 6.17.11-16.17.11-1
linuxlinux_kernel>= 0 < 6.17.0-19.196.17.0-19.19
linuxlinux_kernel>= 6.17.9 < 6.17.116.17.11

CVSS provenance

osv7.2HIGH
vendor_ubuntu7.2HIGH
vendor_redhat5.5MEDIUM
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