cbcvebase.
CVE-2025-37890
published 2025-05-16

CVE-2025-37890: In the Linux kernel, the following vulnerability has been resolved: net_sched: hfsc: Fix a UAF vulnerability in class with netem as child qdisc As described in…

PriorityP337high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.17%
6.7th percentile
In the Linux kernel, the following vulnerability has been resolved: net_sched: hfsc: Fix a UAF vulnerability in class with netem as child qdisc As described in Gerrard's report [1], we have a UAF case when an hfsc class has a netem child qdisc. The crux of the issue is that hfsc is assuming that checking for cl->qdisc->q.qlen == 0 guarantees that it hasn't inserted the class in the vttree or eltree (which is not true for the netem duplicate case). This patch checks the n_active class variable to make sure that the code won't insert the class in the vttree or eltree twice, catering for the reentrant case. [1] https://lore.kernel.org/netdev/CAHcdcOm+03OD2j6R0=YHKqmy=VgJ8xEOKuP6c7mSgnp-TEJJbw@mail.gmail.com/

Affected

49 ranges· showing 25
VendorProductVersion rangeFixed in
debiandebian_linux
debianlinux< linux 6.1.140-1 (bookworm)linux 6.1.140-1 (bookworm)
debianlinux-6.1< linux 6.1.140-1 (bookworm)linux 6.1.140-1 (bookworm)
googlechrome_chrome
linuxlinux
linuxlinux>= 37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea < 273bbcfa53541cde38b2003ad88a59b770306421273bbcfa53541cde38b2003ad88a59b770306421
linuxlinux>= 37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea < e0cf8ee23e1915431f262a7b2dee0c7a7d699af0e0cf8ee23e1915431f262a7b2dee0c7a7d699af0
linuxlinux>= 37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea < e3e949a39a91d1f829a4890e7dfe9417ac72e4d0e3e949a39a91d1f829a4890e7dfe9417ac72e4d0
linuxlinux>= 37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea < 8df7d37d626430035b413b97cee18396b3450bef8df7d37d626430035b413b97cee18396b3450bef
linuxlinux>= 37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea < 6082a87af4c52f58150d40dec1716011d871ac216082a87af4c52f58150d40dec1716011d871ac21
linuxlinux>= 37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea < 2e7093c7a8aba5d4f8809f271488e5babe75e2022e7093c7a8aba5d4f8809f271488e5babe75e202
linuxlinux>= 37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea < ac39fd4a757584d78ed062d4f6fd913f83bd98b5ac39fd4a757584d78ed062d4f6fd913f83bd98b5
linuxlinux>= 37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea < 141d34391abbb315d68556b7c67ad97885407547141d34391abbb315d68556b7c67ad97885407547
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.10.244-15.10.244-1

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv8.8HIGH
vendor_ubuntu8.8HIGH
vendor_debian7.8HIGH
vendor_msrc7.8HIGH
vendor_redhat7.8HIGH
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