MEDIUM · 5.5

CVE-2025-21636

In the Linux kernel, the following vulnerability has been resolved: sctp: sysctl: plpmtud_probe_interval: avoid using current->nsproxy As mentioned in a previous commit of this series, using the 'ne...

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: sctp: sysctl: plpmtud_probe_interval: avoid using current->nsproxy As mentioned in a previous commit of this series, using the 'net' structure via 'current' is not recommended for different reasons: - Inconsistency: getting info from the reader's/writer's netns vs only from the opener's netns. - current->nsproxy can be NULL in some cases, resulting in an 'Oops' (null-ptr-deref), e.g. when the current task is exiting, as spotted by syzbot [1] using acct(2). The 'net' structure can be obtained from the table->data using container_of(). Note that table->data could also be used directly, as this is the only member needed from the 'net' structure, but that would increase the size of this fix, to use '*data' everywhere 'net->sctp.probe_interval' is used.

CVSS Score

5.5

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH

Affected Products

VendorProductVersions
LinuxLinux Kernel>= 5.14, < 5.15.177

Related Weaknesses (CWE)

References

FAQ

What is CVE-2025-21636?

CVE-2025-21636 is a vulnerability with a CVSS score of 5.5 (MEDIUM). In the Linux kernel, the following vulnerability has been resolved: sctp: sysctl: plpmtud_probe_interval: avoid using current->nsproxy As mentioned in a previous commit of this series, using the 'ne...

How severe is CVE-2025-21636?

CVE-2025-21636 has been rated MEDIUM with a CVSS base score of 5.5/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2025-21636?

Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel.