CyberSecBulletin
CVE-2024-49900NVD status: Modified

Linux: Use of Uninitialized Resource

Published Updated By the CyberSecBulletin desk

CVE-2024-49900 is a high-severity use of uninitialized resource vulnerability in Linux, with a CVSS 3.1 base score of 7.1 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions 7b24d41d47a6805c45378debf8bd115675d41da8, dac398ed272a378d2f42ac68ae408333a51baf52, 8b1dcf25c26d42e4a68c4725ce52a0543c7878cc as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.28% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Linux to 7b24d41d47a6805c45378debf8bd115675d41da8 or dac398ed272a378d2f42ac68ae408333a51baf52 or 8b1dcf25c26d42e4a68c4725ce52a0543c7878cc or d7444f91a9f93eaa48827087ed0f3381c194181d, whichever matches your release line, or a later version.
  2. Update SIMATIC S7-1500 TM MFP - GNU/Linux subsystem to V1.1.1 or a later version.
  3. Update Linux Kernel to 5.10.227 or 5.15.168 or 6.1.113 or 6.6.55, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 7b24d41d47a6805c45378debf8bd115675d41da8; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, dac398ed272a378d2f42ac68ae408333a51baf52; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 8b1dcf25c26d42e4a68c4725ce52a0543c7878cc; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, d7444f91a9f93eaa48827087ed0f3381c194181d; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 6041536d18c5f51a84bc37cd568cbab61870031e; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, c076b3746224982eebdba5c9e4b1467e146c0d64; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 7c244d5b48284a770d96ff703df2dfeadf804a73; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 8ad8b531de79c348bcb8133e7f5e827b884226af; and 2 more ranges7b24d41d47a6805c45378debf8bd115675d41da8, dac398ed272a378d2f42ac68ae408333a51baf52, 8b1dcf25c26d42e4a68c4725ce52a0543c7878cc, d7444f91a9f93eaa48827087ed0f3381c194181d, 6041536d18c5f51a84bc37cd568cbab61870031e, c076b3746224982eebdba5c9e4b1467e146c0d64
SiemensSIMATIC S7-1500 TM MFP - GNU/Linux subsystembefore V1.1.1V1.1.1
LinuxLinux Kernelbefore 5.10.227; 5.11 up to, but not including, 5.15.168; 5.16 up to, but not including, 6.1.113; 6.2 up to, but not including, 6.6.55; 6.7 up to, but not including, 6.10.14; 6.11 up to, but not including, 6.11.35.10.227, 5.15.168, 6.1.113, 6.6.55, 6.10.14, 6.11.3

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H. Scored by NVD.

Official description

In the Linux kernel, the following vulnerability has been resolved: jfs: Fix uninit-value access of new_ea in ea_buffer syzbot reports that lzo1x_1_do_compress is using uninit-value: ===================================================== BUG: KMSAN: uninit-value in lzo1x_1_do_compress+0x19f9/0x2510 lib/lzo/lzo1x_compress.c:178 ... Uninit was stored to memory at: ea_put fs/jfs/xattr.c:639 [inline] ... Local variable ea_buf created at: __jfs_setxattr+0x5d/0x1ae0 fs/jfs/xattr.c:662 __jfs_xattr_set+0xe6/0x1f0 fs/jfs/xattr.c:934 ===================================================== The reason is ea_buf->new_ea is not initialized properly. Fix this by using memset to empty its content at the beginning in ea_get().

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Use of Uninitialized Resource

The product uses or accesses a resource that has not been initialized.

How developers prevent this class of flaw

  • Explicitly initialize the resource before use. If this is performed through an API function or standard procedure, follow all required steps.
  • Pay close attention to complex conditionals that affect initialization, since some branches might not perform the initialization.
  • Avoid race conditions (CWE-362) during initialization routines.

More Use of Uninitialized Resource vulnerabilities (CWE-908)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Use of Uninitialized Resource vulnerabilities

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