CyberSecBulletin
CVE-2025-68819NVD status: Deferred

Linux: Out-of-bounds Write

Published Updated By the CyberSecBulletin desk

CVE-2025-68819 is a high-severity out-of-bounds write vulnerability in Linux, with a CVSS 3.1 base score of 7.8 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 c2c293ea7b61f12cdaad1e99a5b4efc58c88960a, c2305b4c5fc15e20ac06c35738e0578eb4323750, 61f214a878e96e2a8750bf96a98f78c658dba60c 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 0.15% 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 c2c293ea7b61f12cdaad1e99a5b4efc58c88960a or c2305b4c5fc15e20ac06c35738e0578eb4323750 or 61f214a878e96e2a8750bf96a98f78c658dba60c or 4a54d8fcb093761e4c56eb211cf4e39bf8401fa1, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux60688d5e6e6e2ae62f29762d1e3b2aec2dbd3817 up to, but not including, c2c293ea7b61f12cdaad1e99a5b4efc58c88960a; 60688d5e6e6e2ae62f29762d1e3b2aec2dbd3817 up to, but not including, c2305b4c5fc15e20ac06c35738e0578eb4323750; 60688d5e6e6e2ae62f29762d1e3b2aec2dbd3817 up to, but not including, 61f214a878e96e2a8750bf96a98f78c658dba60c; 60688d5e6e6e2ae62f29762d1e3b2aec2dbd3817 up to, but not including, 4a54d8fcb093761e4c56eb211cf4e39bf8401fa1; 60688d5e6e6e2ae62f29762d1e3b2aec2dbd3817 up to, but not including, fe3e129ab49806aaaa3f22067ebc75c2dfbe4658; 60688d5e6e6e2ae62f29762d1e3b2aec2dbd3817 up to, but not including, ac92151ff2494130d9fc686055d6bbb9743a673e; 60688d5e6e6e2ae62f29762d1e3b2aec2dbd3817 up to, but not including, b91e6aafe8d356086cc621bc03e35ba2299e4788; 2.6.28c2c293ea7b61f12cdaad1e99a5b4efc58c88960a, c2305b4c5fc15e20ac06c35738e0578eb4323750, 61f214a878e96e2a8750bf96a98f78c658dba60c, 4a54d8fcb093761e4c56eb211cf4e39bf8401fa1, fe3e129ab49806aaaa3f22067ebc75c2dfbe4658, ac92151ff2494130d9fc686055d6bbb9743a673e

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
HighData or code can be modified at will.
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:H/A:H. Scored by CNA.

Official description

In the Linux kernel, the following vulnerability has been resolved: media: dvb-usb: dtv5100: fix out-of-bounds in dtv5100_i2c_msg() rlen value is a user-controlled value, but dtv5100_i2c_msg() does not check the size of the rlen value. Therefore, if it is set to a value larger than sizeof(st->data), an out-of-bounds vuln occurs for st->data. Therefore, we need to add proper range checking to prevent this vuln.

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: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Out-of-bounds Write vulnerabilities

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