CVE-2025-38465: debian linux — Fix

Description

In the Linux kernel, the following vulnerability has been resolved: netlink: Fix wraparounds of sk->sk_rmem_alloc. Netlink has this pattern in some places if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf) atomic_add(skb->truesize, &sk->sk_rmem_alloc); , which has the same problem fixed by commit 5a465a0da13e ("udp: Fix multiple wraparounds of sk->sk_rmem_alloc."). For example, if we set INT_MAX to SO_RCVBUFFORCE, the condition is always false as the two operands are of int. Then, a single socket can eat as many skb as possible until OOM happens, and we can see multiple wraparounds of sk->sk_rmem_alloc. Let's fix it by using atomic_add_return() and comparing the two variables as unsigned int. Before: [root@fedora ~]# ss -f netlink Recv-Q Send-Q Local Address:Port Peer Address:Port -1668710080 0 rtnl:nl_wraparound/293 * After: [root@fedora ~]# ss -f netlink Recv-Q Send-Q Local Address:Port Peer Address:Port 2147483072 0 rtnl:nl_wraparound/290 * ^ `--- INT_MAX - 576

Is your site exposed to CVE-2025-38465?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

5.5

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-401 CWE-401

Affected Products

Vendor	Product	Versions
linux	linux_kernel	2.6.13 — 5.4.296
linux	linux_kernel	5.5 — 5.10.240
linux	linux_kernel	5.11 — 5.15.189
linux	linux_kernel	5.16 — 6.1.146
linux	linux_kernel	6.2 — 6.6.99
linux	linux_kernel	6.7 — 6.12.39
linux	linux_kernel	6.13 — 6.15.7
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
debian	debian_linux	All

References

Advisories & Patches

https://git.kernel.org/stable/c/4b8e18af7bea92f8b7fb92d40aeae729209db250 https://git.kernel.org/stable/c/55baecb9eb90238f60a8350660d6762046ebd3bd https://git.kernel.org/stable/c/76602d8e13864524382b0687dc32cd8f19164d5a https://git.kernel.org/stable/c/9da025150b7c14a8390fc06aea314c0a4011e82c https://git.kernel.org/stable/c/ae8f160e7eb24240a2a79fc4c815c6a0d4ee16cc https://git.kernel.org/stable/c/c4ceaac5c5ba0b992ee1dc88e2a02421549e5c98 https://git.kernel.org/stable/c/cd7ff61bfffd7000143c42bbffb85eeb792466d6 https://git.kernel.org/stable/c/fd69af06101090eaa60b3d216ae715f9c0a58e5b

Other References

https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html https://cert-portal.siemens.com/productcert/html/ssa-082556.html

Frequently Asked Questions

What is CVE-2025-38465? +

In the Linux kernel, the following vulnerability has been resolved: netlink: Fix wraparounds of sk->sk_rmem_alloc. Netlink has this pattern in some places if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf) atomic_add(skb->truesize, &sk->sk_rmem_alloc); , which has the same problem fixed by commit 5a465a0da13e ("udp: Fix multiple wraparounds of sk->sk_rmem_alloc."). For example, if we set INT_MAX to SO_RCVBUFFORCE, the condition is always false as the two operands are of int. Then, a single socket can eat as many skb as possible until OOM happens, and we can see multiple wraparounds of sk->sk_rmem_alloc. Let's fix it by using atomic_add_return() and comparing the two variables as unsigned int. Before: [root@fedora ~]# ss -f netlink Recv-Q Send-Q Local Address:Port Peer Address:Port -1668710080 0 rtnl:nl_wraparound/293 * After: [root@fedora ~]# ss -f netlink Recv-Q Send-Q Local Address:Port Peer Address:Port 2147483072 0 rtnl:nl_wraparound/290 * ^ `--- INT_MAX - 576 It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2025-38465? +

CVE-2025-38465 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2025-38465? +

CVE-2025-38465 affects products from debian, linux, specifically: debian_linux, linux_kernel. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-38465? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2026-0646

A denial-of-service security issue exists within the 1794-AENTR adapter due to improper memory handling of CIP protocol requests. This vulnerability …

CVE-2026-20746

Virtual attribute handling in Ping Identity PingDirectory in affected versions allows only authorized users to exhaust java memory heap when …

CVE-2026-53429

Missing Release of Memory after Effective Lifetime vulnerability in leandrocp mdex and mdex_native allows an attacker who controls a rendered …

CVE-2024-25450 8.8

imlib2 v1.9.1 was discovered to mishandle memory allocation in the function init_imlib_fonts().

CVE-2025-20133 8.6

A vulnerability in the management and VPN web servers of the Remote Access SSL VPN feature of Cisco Secure Firewall …

CVE-2025-20239 8.6

A vulnerability in the Internet Key Exchange Version 2 (IKEv2) feature of Cisco IOS Software, IOS XE Software, Secure Firewall …

CVE-2025-38465