CVE-2025-37890: Linux hwe edge · 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
Affects linux-hwe-edgeSource GCVE Database
Mentioned vulnerabilities
Not known to be exploited · CVSS 7.8 Medium · patch available : update linux-hwe-edge when convenient.
Data as of 26 Oct 2026, 06:26 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 12% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 16 May 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-26.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Red Hatredhat/kernel-livepatchpkg:rpm/redhat/kernel-livepatchOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
An official patch is available as the kpatch-patch-5_14_0-570_17_1 live patch module for Red Hat Enterprise Linux 9 kernel 5.14.0-570.17.1.el9_6. Users should apply this update promptly following Red Hat's guidance at https://access.redhat.com/articles/11258. A system reboot is required for the update to take effect. No additional mitigation steps are indicated by the vendor advisory.
Description
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/
References
- access.redhat.com/errata/RHSA-2025:16538 (opens in a new tab)
- access.redhat.com/security/updates/classification/ (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2366848 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2370776 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2370786 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2382054 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2383381 (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/advisories/2025/rhsa-2025_16538.json (opens in a new tab)
- ubuntu.com/security/CVE-2025-37890 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-37890 (opens in a new tab)
- git.kernel.org/linus/141d34391abbb315d68556b7c67ad97885407547 (opens in a new tab)
- git.kernel.org/stable/c/141d34391abbb315d68556b7c67ad97885407547 (opens in a new tab)
- git.kernel.org/stable/c/2e7093c7a8aba5d4f8809f271488e5babe75e202 (opens in a new tab)
- git.kernel.org/stable/c/6082a87af4c52f58150d40dec1716011d871ac21 (opens in a new tab)
- git.kernel.org/stable/c/8df7d37d626430035b413b97cee18396b3450bef (opens in a new tab)
- git.kernel.org/stable/c/ac39fd4a757584d78ed062d4f6fd913f83bd98b5 (opens in a new tab)
- git.kernel.org/stable/c/e3e949a39a91d1f829a4890e7dfe9417ac72e4d0 (opens in a new tab)
- ubuntu.com/security/notices/USN-7608-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7608-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7608-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7609-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7609-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7610-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7611-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7608-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-7609-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7618-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7608-5 (opens in a new tab)