CVE-2024-46800
sch/netem: fix use after free in netem_dequeue
In the Linux kernel, the following vulnerability has been resolved:sch/netem: fix use after free in netem_dequeueIf netem_dequeue() enqueues packet to inner qdisc and that qdiscreturns __NET_XMIT_STOLEN. The packet is dropped butqdisc_tree_reduce_backlog() is not called to update the parent'sq.qlen, leading to the similar use-after-free as Commite04991a48dbaf382 ("netem: fix return value if duplicate enqueuefails")Commands to trigger KASAN UaF:ip link add type dummyip link set lo upip link set dummy0 uptc qdisc add dev lo parent root handle 1: drrtc filter add dev lo parent 1: basic classid 1:1tc class add dev lo classid 1:1 drrtc qdisc add dev lo parent 1:1 handle 2: netemtc qdisc add dev lo parent 2: handle 3: drrtc filter add dev lo parent 3: basic classid 3:1 action mirred egressredirect dev dummy0tc class add dev lo classid 3:1 drrping -c1 -W0.01 localhost # Trigger bugtc class del dev lo classid 1:1tc class add dev lo classid 1:1 drrping -c1 -W0.01 localhost # UaF
- Affected
- Linux
- CVSS v3.1 NVD
- 7.8 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS
- 0.27% chance of exploitation in the next 30 days, 17th percentile
- Published
- 2024-09-18
- Updated
- 2026-08-05
Exploit collections (1)
- linux/kernelctf/CVE-2024-46800_lts_cos_mitigationgoogle/security-research
Security advisories
- https://git.kernel.org/stable/c/14f91ab8d391f249b845916820a56f42cf747241
- https://git.kernel.org/stable/c/295ad5afd9efc5f67b86c64fce28fb94e26dc4c9
- https://git.kernel.org/stable/c/32008ab989ddcff1a485fa2b4906234c25dc5cd6
- https://git.kernel.org/stable/c/3b3a2a9c6349e25a025d2330f479bc33a6ccb54a
- https://git.kernel.org/stable/c/98c75d76187944296068d685dfd8a1e9fd8c4fdc
- https://git.kernel.org/stable/c/db2c235682913a63054e741fe4e19645fdf2d68e
- https://git.kernel.org/stable/c/dde33a9d0b80aae0c69594d1f462515d7ff1cb3d
- https://git.kernel.org/stable/c/f0bddb4de043399f16d1969dad5ee5b984a64e7b