CVE-2025-21703
netem: Update sch->q.qlen before qdisc_tree_reduce_backlog()
Description
In the Linux kernel, the following vulnerability has been resolved: netem: Update sch->q.qlen before qdisc_tree_reduce_backlog() qdisc_tree_reduce_backlog() notifies parent qdisc only if child qdisc becomes empty, therefore we need to reduce the backlog of the child qdisc before calling it. Otherwise it would miss the opportunity to call cops->qlen_notify(), in the case of DRR, it resulted in UAF since DRR uses ->qlen_notify() to maintain its active list.
No summary for this CVE yet.
CVSS Vector Breakdown
Exploitability
AV:LAttack VectorLocal
AC:LAttack ComplexityLow
PR:LPrivileges RequiredLow
UI:NUser InteractionNone
Scope
S:UScopeUnchanged
Impact
C:HConfidentialityHigh
I:HIntegrityHigh
A:HAvailabilityHigh
Weaknesses
Affected Products
Linux
oss-projectaka the linux kernel
ООО «РусБИТех-Астра»
commercial·RUaka rusbitech-astra
Сообщество свободного программного обеспечения
oss-projectaka fsf
АО «НППКТ»
commercial·RU
Oracle Corp.
commercial·USaka oracle
and 1 more affected products View all →
Exploitability
Official Patch Available
Workaround Available
Attack Graph
Products CVE Techniques Tactics
Click technique nodes for MITRE ATT&CK details · drag to pan · Ctrl/⌘ + scroll to zoom, or go fullscreen.
MITRE ATT&CK
2 techniques Initial Access
Privilege Escalation
References
https://git.kernel.org/stable/c/1f8e3f4a4b8b90ad274dfbc66fc7d55cb582f4d5
git.kernel.org
https://git.kernel.org/stable/c/6312555249082d6d8cc5321ff725df05482d8b83
git.kernel.org
https://git.kernel.org/stable/c/638ba5089324796c2ee49af10427459c2de35f71
git.kernel.org
and 34 more references View all →
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