CyberSecBulletin
CVE-2024-42094NVD status: Modified

Linux: Out-of-bounds Write

Published Updated By the CyberSecBulletin desk

CVE-2024-42094 is a high-severity out-of-bounds write 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 2b085521be5292016097b5e7ca81b26be3f7098d, 842afb47d84536fc976fece8fb6c54bea711ad1a, 9dadab0db7d904413ea1cdaa13f127da05c31e71 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 0.24% 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 2b085521be5292016097b5e7ca81b26be3f7098d or 842afb47d84536fc976fece8fb6c54bea711ad1a or 9dadab0db7d904413ea1cdaa13f127da05c31e71 or 0af718a690acc089aa1bbb95a93df833d864ef53, whichever matches your release line, or a later version.
  2. Update RUGGEDCOM RST2428P to V3.1 or a later version.
  3. Update SCALANCE XCM-/XRM-/XCH-/XRH-300 family to V3.1 or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux2356f4cb191100a5e92d537f13e5efdbc697e9cb up to, but not including, 2b085521be5292016097b5e7ca81b26be3f7098d; 2356f4cb191100a5e92d537f13e5efdbc697e9cb up to, but not including, 842afb47d84536fc976fece8fb6c54bea711ad1a; 2356f4cb191100a5e92d537f13e5efdbc697e9cb up to, but not including, 9dadab0db7d904413ea1cdaa13f127da05c31e71; 2356f4cb191100a5e92d537f13e5efdbc697e9cb up to, but not including, 0af718a690acc089aa1bbb95a93df833d864ef53; 2356f4cb191100a5e92d537f13e5efdbc697e9cb up to, but not including, d85ca8179a54ff8cf1e1f8c3c9e3799831319bae; 2356f4cb191100a5e92d537f13e5efdbc697e9cb up to, but not including, 724e7965af054079242b8d6f7e50ee226730a756; 2356f4cb191100a5e92d537f13e5efdbc697e9cb up to, but not including, 2d090c7f7be3b26fcb80ac04d08a4a8062b1d959; 2356f4cb191100a5e92d537f13e5efdbc697e9cb up to, but not including, be4e1304419c99a164b4c0e101c7c2a756b635b9; and 1 more ranges2b085521be5292016097b5e7ca81b26be3f7098d, 842afb47d84536fc976fece8fb6c54bea711ad1a, 9dadab0db7d904413ea1cdaa13f127da05c31e71, 0af718a690acc089aa1bbb95a93df833d864ef53, d85ca8179a54ff8cf1e1f8c3c9e3799831319bae, 724e7965af054079242b8d6f7e50ee226730a756
SiemensRUGGEDCOM RST2428Pbefore V3.1V3.1
SiemensSCALANCE XC-300/XR-300/XC-400/XR-500WG/XR-500 familyNot specified in the recordNot stated
SiemensSCALANCE XCM-/XRM-/XCH-/XRH-300 familybefore V3.1V3.1
SiemensSIMATIC S7-1500 TM MFP - GNU/Linux subsystembefore V1.1.1V1.1.1
LinuxLinux Kernelbefore 4.19.317; 4.20 up to, but not including, 5.4.279; 5.5 up to, but not including, 5.10.221; 5.11 up to, but not including, 5.15.162; 5.16 up to, but not including, 6.1.97; 6.2 up to, but not including, 6.6.37; 6.7 up to, but not including, 6.9.84.19.317, 5.4.279, 5.10.221, 5.15.162, 6.1.97, 6.6.37

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: net/iucv: Avoid explicit cpumask var allocation on stack For CONFIG_CPUMASK_OFFSTACK=y kernel, explicit allocation of cpumask variable on stack is not recommended since it can cause potential stack overflow. Instead, kernel code should always use *cpumask_var API(s) to allocate cpumask var in config-neutral way, leaving allocation strategy to CONFIG_CPUMASK_OFFSTACK. Use *cpumask_var API(s) to address it.

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

The underlying weakness: Out-of-bounds Write

The product writes data past the end, or before the beginning, of the intended buffer.

How developers prevent this class of flaw

  • Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, many languages that perform their own memory management, such as Java and Perl, are not subject to buffer overflows. Other languages, such as Ada and C#, typically provide overflow protection, but the protection can be disabled by the programmer. Be wary that a language's interface to native code may still be subject to overflows, even if the language itself is theoretically safe.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Examples include the Safe C String Library (SafeStr) by Messier and Viega, and the Strsafe.h library from Microsoft. These libraries provide safer versions of overflow-prone string-handling functions.
  • Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking. D3-SFCV (Stack Frame Canary Validation) from D3FEND discusses canary-based detection in detail.

More Out-of-bounds Write vulnerabilities (CWE-787)

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 Out-of-bounds Write vulnerabilities

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