afs: Fix UAF when sending a message
In the Linux kernel, the following vulnerability has been resolved: afs: Fix UAF when sending a message In afs_make_call(), there's a race with async call reception and destruction. If a call is dispatched that doesn't have call->write_iter set (used to specify the data content for FS.StoreData), then the first rxrpc_kernel_send_data() will not set MSG_MORE in the msghdr. Once rxrpc_send_data() queues the last request packet, the response could come in at any time and cause the call to be completed and put. However, afs_make_call() will look at the call again to see it ->write_iter should be handled - something it's only allowed to do if it has its own ref on the call. Whilst this is the case for synchronous calls, it isn't true for async calls such as FS.FetchData. There's also a potential UAF in afs_make_call() in the event that an asynchronous call is being sent, but the call fails in some way (e.g. it gets aborted from the server). The problem there is that afs_make_call() tries to abort a call if the rxrpc send fails, but the asynchronous notification from rxrpc may have caused the afs_call to be torn down. generic/650 plays games with randomly taking CPUs offline, and can interject a significant delay such that the call is deallocated before afs_make_call() gets to check call->write_iter - and a UAF ensues (caught by KASAN). BUG: KASAN: slab-use-after-free in afs_make_call+0x1c90/0x2210 [kafs] Read of size 8 at addr ffff888035e050e8 by task fsstress/1409 Fix this by mak
CVE-2026-74506
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-74506
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "e49c7b2f6de7ff81ca34c56e4eeb4fa740c099f2",
"lessThan": "cbb0d3da042c01082f40166fdc99bf1752db72be",
"versionType": "git"
},
{
"status": "affected",
"version": "e49c7b2f6de7ff81ca34c56e4eeb4fa740c099f2",
"lessThan": "c0d3b81f703b2a9e37fe1347610a50cdf0078c27",
"versionType": "git"
},
{
"status": "affected",
"version": "e49c7b2f6de7ff81ca34c56e4eeb4fa740c099f2",
"lessThan": "daaa726b14fc3026a6b328614d312b698f62f391",
"versionType": "git"
},
{
"status": "affected",
"version": "e49c7b2f6de7ff81ca34c56e4eeb4fa740c099f2",
"lessThan": "4af1ec68d54b3871155914d584fb10669c41a861",
"versionType": "git"
}
],
"programFiles": [
"fs/afs/internal.h"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5.8"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.8",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.12.114",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.44",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.8",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"fs/afs/internal.h"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-74506
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #46562 · Revision 1
- Added to Heist Feed
- Publisher date