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 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/
Configurations

Configuration 1 (hide)

OR cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.0:-:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.0:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.0:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.0:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.0:rc6:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.0:rc7:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.0:rc8:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.15:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.15:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.15:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.15:rc4:*:*:*:*:*:*

Configuration 2 (hide)

cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*

History

17 Nov 2025, 17:11

Type Values Removed Values Added
CWE CWE-416
First Time Linux linux Kernel
Debian
Debian debian Linux
Linux
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 7.8
CPE cpe:2.3:o:linux:linux_kernel:5.0:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.15:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.0:rc4:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.15:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.0:rc7:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.15:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.0:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.15:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.0:rc6:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.0:-:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.0:rc8:*:*:*:*:*:*
References () https://git.kernel.org/stable/c/141d34391abbb315d68556b7c67ad97885407547 - () https://git.kernel.org/stable/c/141d34391abbb315d68556b7c67ad97885407547 - Patch
References () https://git.kernel.org/stable/c/273bbcfa53541cde38b2003ad88a59b770306421 - () https://git.kernel.org/stable/c/273bbcfa53541cde38b2003ad88a59b770306421 - Patch
References () https://git.kernel.org/stable/c/2e7093c7a8aba5d4f8809f271488e5babe75e202 - () https://git.kernel.org/stable/c/2e7093c7a8aba5d4f8809f271488e5babe75e202 - Patch
References () https://git.kernel.org/stable/c/6082a87af4c52f58150d40dec1716011d871ac21 - () https://git.kernel.org/stable/c/6082a87af4c52f58150d40dec1716011d871ac21 - Patch
References () https://git.kernel.org/stable/c/8df7d37d626430035b413b97cee18396b3450bef - () https://git.kernel.org/stable/c/8df7d37d626430035b413b97cee18396b3450bef - Patch
References () https://git.kernel.org/stable/c/ac39fd4a757584d78ed062d4f6fd913f83bd98b5 - () https://git.kernel.org/stable/c/ac39fd4a757584d78ed062d4f6fd913f83bd98b5 - Patch
References () https://git.kernel.org/stable/c/e0cf8ee23e1915431f262a7b2dee0c7a7d699af0 - () https://git.kernel.org/stable/c/e0cf8ee23e1915431f262a7b2dee0c7a7d699af0 - Patch
References () https://git.kernel.org/stable/c/e3e949a39a91d1f829a4890e7dfe9417ac72e4d0 - () https://git.kernel.org/stable/c/e3e949a39a91d1f829a4890e7dfe9417ac72e4d0 - Patch
References () https://lists.debian.org/debian-lts-announce/2025/08/msg00010.html - () https://lists.debian.org/debian-lts-announce/2025/08/msg00010.html - Mailing List
References () https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html - () https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html - Mailing List

03 Nov 2025, 20:18

Type Values Removed Values Added
References
  • () https://lists.debian.org/debian-lts-announce/2025/08/msg00010.html -
  • () https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html -

Information

Published : 2025-05-16 13:15

Updated : 2025-11-17 17:11


NVD link : CVE-2025-37890

Mitre link : CVE-2025-37890

CVE.ORG link : CVE-2025-37890


JSON object : View

Products Affected

linux

  • linux_kernel

debian

  • debian_linux
CWE
CWE-416

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