CyberSecBulletin
CVE-2022-50030NVD status: Analyzed

Linux: Out-of-bounds Write

Published Updated By the CyberSecBulletin desk

CVE-2022-50030 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 927907f1cbb3408cadde637fccfc17bb6b10a87d, c29a4baaad38a332c0ae480cf6d6c5bf75ac1828, b92506dc51f81741eb26609175ac206c20f06e0a 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 927907f1cbb3408cadde637fccfc17bb6b10a87d or c29a4baaad38a332c0ae480cf6d6c5bf75ac1828 or b92506dc51f81741eb26609175ac206c20f06e0a or 2d544e9d19c109dfe34b3dc1253a8b2971abe060, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 5.4.211 or 5.10.138 or 5.15.63 or 5.19.4, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinuxbd2cdd5e400f5914bc30d5cfb0a0185cf51e4424 up to, but not including, 927907f1cbb3408cadde637fccfc17bb6b10a87d; bd2cdd5e400f5914bc30d5cfb0a0185cf51e4424 up to, but not including, c29a4baaad38a332c0ae480cf6d6c5bf75ac1828; bd2cdd5e400f5914bc30d5cfb0a0185cf51e4424 up to, but not including, b92506dc51f81741eb26609175ac206c20f06e0a; bd2cdd5e400f5914bc30d5cfb0a0185cf51e4424 up to, but not including, 2d544e9d19c109dfe34b3dc1253a8b2971abe060; bd2cdd5e400f5914bc30d5cfb0a0185cf51e4424 up to, but not including, f8191d40aa612981ce897e66cda6a88db8df17bb; 4.11927907f1cbb3408cadde637fccfc17bb6b10a87d, c29a4baaad38a332c0ae480cf6d6c5bf75ac1828, b92506dc51f81741eb26609175ac206c20f06e0a, 2d544e9d19c109dfe34b3dc1253a8b2971abe060, f8191d40aa612981ce897e66cda6a88db8df17bb
LinuxLinux Kernelbefore 5.4.211; 5.5 up to, but not including, 5.10.138; 5.11 up to, but not including, 5.15.63; 5.16 up to, but not including, 5.19.45.4.211, 5.10.138, 5.15.63, 5.19.4

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 NVD.

Official description

In the Linux kernel, the following vulnerability has been resolved: scsi: lpfc: Prevent buffer overflow crashes in debugfs with malformed user input Malformed user input to debugfs results in buffer overflow crashes. Adapt input string lengths to fit within internal buffers, leaving space for NULL terminators.

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

References

Recent Out-of-bounds Write vulnerabilities

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