CVE Catalog

CVE-2024-46800

HighCVSS 7.8
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.27%

19th percentile - higher than 19% of all known CVEs

Summary

In the Linux kernel, the netem queueing discipline has a use-after-free vulnerability in netem_dequeue. When a packet is enqueued to an inner qdisc and returns __NET_XMIT_STOLEN, not updating the qlen counter may lead to use-after-free.

Risk Assessment

The vulnerability may lead to system crash or potentially allow an attacker to execute arbitrary code in kernel context.

Recommendation

It is recommended to apply the official Linux kernel patch that updates the qlen counter when a packet is dropped.

Other vulnerabilities in Linux kernel

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Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: sch/netem: fix use after free in netem_dequeue If netem_dequeue() enqueues packet to inner qdisc and that qdisc returns __NET_XMIT_STOLEN. The packet is dropped but qdisc_tree_reduce_backlog() is not called to update the parent's q.qlen, leading to the similar use-after-free as Commit e04991a48dbaf382 ("netem: fix return value if duplicate enqueue fails") Commands to trigger KASAN UaF: ip link add type dummy ip link set lo up ip link set dummy0 up tc qdisc add dev lo parent root handle 1: drr tc filter add dev lo parent 1: basic classid 1:1 tc class add dev lo classid 1:1 drr tc qdisc add dev lo parent 1:1 handle 2: netem tc qdisc add dev lo parent 2: handle 3: drr tc filter add dev lo parent 3: basic classid 3:1 action mirred egress redirect dev dummy0 tc class add dev lo classid 3:1 drr ping -c1 -W0.01 localhost # Trigger bug tc class del dev lo classid 1:1 tc class add dev lo classid 1:1 drr ping -c1 -W0.01 localhost # UaF

Vulnerability data from NVD (NIST) · CISA KEV · EPSS