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🛡️ CVE-2023-53136 — kernel

🟠 CVSS 7.1 — High ✅ No Known Exploit NVD
7.1
CVSS Score
0 Low4 Medium7 High9 Critical10

Description

af_unix: fix struct pid leaks in OOB support

In the Linux kernel, the following vulnerability has been resolved:

af_unix: fix struct pid leaks in OOB support

syzbot reported struct pid leak [1].

Issue is that queue_oob() calls maybe_add_creds() which potentially

holds a reference on a pid.

But skb->destructor is not set (either directly or by calling

unix_scm_to_skb())

This means that subsequent kfree_skb() or consume_skb() would leak

this reference.

In this fix, I chose to fully support scm even for the OOB message.

[1]

BUG: memory leak

unreferenced object 0xffff8881053e7f80 (size 128):

comm "syz-executor242", pid 5066, jiffies 4294946079 (age 13.220s)

hex dump (first 32 bytes):

01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

backtrace:

[<ffffffff812ae26a>] alloc_pid+0x6a/0x560 kernel/pid.c:180

[<ffffffff812718df>] copy_process+0x169f/0x26c0 kernel/fork.c:2285

[<ffffffff81272b37>] kernel_clone+0xf7/0x610 kernel/fork.c:2684

[<ffffffff812730cc>] __do_sys_clone+0x7c/0xb0 kernel/fork.c:2825

[<ffffffff849ad699>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]

[<ffffffff849ad699>] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80

[<ffffffff84a0008b>] entry_SYSCALL_64_after_hwframe+0x63/0xcd

How this vulnerability can be exploited

This issue can be reached with local access to the system, attack complexity is low, an attacker needs low-level privileges on the target. No user interaction is required. The scope is unchanged, so the impact stays within the vulnerable component. Rated impact: confidentiality high, integrity none, availability high.

CVSS metrics in full

The score comes from this vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

  • Attack vector: Local — a local account, shell or session on the host is needed.
  • Attack complexity: Low — the attack works reliably, with no preparation.
  • Privileges required: Low — an ordinary user account is enough.
  • User interaction: None — nobody has to be tricked into anything.
  • Scope: Unchanged — the damage stays inside the vulnerable component.
  • Confidentiality impact: High — total loss, or loss the attacker controls.
  • Integrity impact: None.
  • Availability impact: High — total loss, or loss the attacker controls.

Affected software

CVE-2023-53136 is recorded against 2 packages.

  • kernel (from 6.2.0 up to 6.2.7)
  • linux-kernel

Timeline and source

Published on 2 May 2025 and last revised on 12 August 2026. No public exploit is currently recorded for this entry. A vendor advisory or fix has been published. Record sourced from NVD.

References

git.kernel.org (Web)
git.kernel.org (Web)
git.kernel.org (Web)
git.kernel.org (Web)
github.com (Advisory)
nvd.nist.gov (Advisory)
git.kernel.org (Package)

Other advisories for this package

kernel has other advisories on record. If you are patching this one, these are worth checking on the same host:

CVE-2023-53136 on other distributions

Each distribution ships its own build and its own fixed version. Pick the one you run:

Details

Severity High
CVSS Score 7.1
CVSS Vector CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
CWE N/A
Public Exploit ✅ No
Source NVD
Published 2025-05-02
Updated 2026-08-20
Modified 2026-08-12

Affected Packages

Software From version Fixed in
kernel 6.2.0 6.2.7
linux-kernel — —

Similar Threats

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ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the vulnerabilities listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.

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