Use After Free Affecting kernel package, versions *


Severity

Recommended
0.0
medium
0
10

Based on CentOS security rating.

Threat Intelligence

EPSS
0.04% (12th percentile)

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  • Snyk IDSNYK-CENTOS8-KERNEL-6545333
  • published4 Apr 2024
  • disclosed3 Apr 2024

Introduced: 3 Apr 2024

CVE-2024-26689  (opens in a new tab)
CWE-416  (opens in a new tab)

How to fix?

There is no fixed version for Centos:8 kernel.

NVD Description

Note: Versions mentioned in the description apply only to the upstream kernel package and not the kernel package as distributed by Centos. See How to fix? for Centos:8 relevant fixed versions and status.

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

ceph: prevent use-after-free in encode_cap_msg()

In fs/ceph/caps.c, in encode_cap_msg(), "use after free" error was caught by KASAN at this line - 'ceph_buffer_get(arg->xattr_buf);'. This implies before the refcount could be increment here, it was freed.

In same file, in "handle_cap_grant()" refcount is decremented by this line - 'ceph_buffer_put(ci->i_xattrs.blob);'. It appears that a race occurred and resource was freed by the latter line before the former line could increment it.

encode_cap_msg() is called by __send_cap() and __send_cap() is called by ceph_check_caps() after calling __prep_cap(). __prep_cap() is where arg->xattr_buf is assigned to ci->i_xattrs.blob. This is the spot where the refcount must be increased to prevent "use after free" error.

CVSS Scores

version 3.1