CVE-2025-37890
net_sched: hfsc: Fix a UAF vulnerability in class with netem as child qdisc
Severity Score
Exploit Likelihood
Affected Versions
Public Exploits
0Exploited in Wild
-Decision
Descriptions
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/
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/
Several vulnerabilities have been discovered in the Linux kernel that may lead to a privilege escalation, denial of service or information leaks.
CVSS Scores
SSVC
- Decision:-
Timeline
- 2025-04-16 CVE Reserved
- 2025-05-16 CVE Published
- 2025-06-04 CVE Updated
- 2025-06-17 EPSS Updated
- ---------- Exploited in Wild
- ---------- KEV Due Date
- ---------- First Exploit
CWE
CAPEC
References (9)
| URL | Tag | Source |
|---|---|---|
| https://git.kernel.org/stable/c/37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea | Vuln. Introduced |
| URL | Date | SRC |
|---|
| URL | Date | SRC |
|---|
Affected Vendors, Products, and Versions
| Vendor | Product | Version | Other | Status | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Vendor | Product | Version | Other | Status | <-- --> | Vendor | Product | Version | Other | Status |
| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 5.0 < 5.4.294 Search vendor "Linux" for product "Linux Kernel" and version " >= 5.0 < 5.4.294" | en |
Affected
| ||||||
| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 5.0 < 5.10.238 Search vendor "Linux" for product "Linux Kernel" and version " >= 5.0 < 5.10.238" | en |
Affected
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| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 5.0 < 5.15.182 Search vendor "Linux" for product "Linux Kernel" and version " >= 5.0 < 5.15.182" | en |
Affected
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| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 5.0 < 6.1.138 Search vendor "Linux" for product "Linux Kernel" and version " >= 5.0 < 6.1.138" | en |
Affected
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| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 5.0 < 6.6.90 Search vendor "Linux" for product "Linux Kernel" and version " >= 5.0 < 6.6.90" | en |
Affected
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| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 5.0 < 6.12.28 Search vendor "Linux" for product "Linux Kernel" and version " >= 5.0 < 6.12.28" | en |
Affected
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| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 5.0 < 6.14.6 Search vendor "Linux" for product "Linux Kernel" and version " >= 5.0 < 6.14.6" | en |
Affected
| ||||||
| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 5.0 < 6.15 Search vendor "Linux" for product "Linux Kernel" and version " >= 5.0 < 6.15" | en |
Affected
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