CVE-2025-21636
Linux Kernel SCTP sysctl NULL Pointer Dereference 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.
INFO
Published Date :
Jan. 19, 2025, 11:15 a.m.
Last Modified :
Feb. 27, 2025, 9:59 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update the Linux kernel to the latest stable version.
- Apply the specific patch addressing the sctp sysctl issue.
- Verify the kernel version after applying the updates.
Public PoC/Exploit Available at Github
CVE-2025-21636 has a 1 public
PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2025-21636.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2025-21636 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2025-21636
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
None
Java
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2025-21636 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2025-21636 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Feb. 27, 2025
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Added CWE CWE-476 Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:6.13:rc2:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.13:rc1:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.13:rc3:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.13:rc4:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.13:rc5:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.13:rc6:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.14 from (excluding) 5.15.177 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.16 from (excluding) 6.1.125 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.2 from (excluding) 6.6.72 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.7 from (excluding) 6.12.10 Added Reference Type kernel.org: https://git.kernel.org/stable/c/1dc5da6c4178f3e4b95c631418f72de9f86c0449 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/284a221f8fa503628432c7bb5108277c688c6ffa Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/44ee8635922b6eb940faddb961a8347c6857d722 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/6259d2484d0ceff42245d1f09cc8cb6ee72d847a Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/bcf8c60074e81ed2ac2d35130917175a3949c917 Types: Patch -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jan. 23, 2025
Action Type Old Value New Value Added Reference https://git.kernel.org/stable/c/1dc5da6c4178f3e4b95c631418f72de9f86c0449 -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jan. 19, 2025
Action Type Old Value New Value Added 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. Added Reference https://git.kernel.org/stable/c/284a221f8fa503628432c7bb5108277c688c6ffa Added Reference https://git.kernel.org/stable/c/44ee8635922b6eb940faddb961a8347c6857d722 Added Reference https://git.kernel.org/stable/c/6259d2484d0ceff42245d1f09cc8cb6ee72d847a Added Reference https://git.kernel.org/stable/c/bcf8c60074e81ed2ac2d35130917175a3949c917