CyberSecBulletin
CVE-2023-53077NVD status: Analyzed

Linux: Out-of-bounds Write

Published Updated By the CyberSecBulletin desk

CVE-2023-53077 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 7257070be70e19a9138f39009c1a26c83a8a7cfa, bec1bea2fa974e63f6059c33edde669c7894d0bc, a16394b5d661afec9a264fecac3abd87aea439ea 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 0.21% 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 7257070be70e19a9138f39009c1a26c83a8a7cfa or bec1bea2fa974e63f6059c33edde669c7894d0bc or a16394b5d661afec9a264fecac3abd87aea439ea or e12b95680821b9880cd9992c0f3555389363604f, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 5.10.176 or 5.15.104 or 6.1.21 or 6.2.8, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux6725a88f88a7e922e91c45bf83d320487810c192 up to, but not including, 7257070be70e19a9138f39009c1a26c83a8a7cfa; 6725a88f88a7e922e91c45bf83d320487810c192 up to, but not including, bec1bea2fa974e63f6059c33edde669c7894d0bc; 6725a88f88a7e922e91c45bf83d320487810c192 up to, but not including, a16394b5d661afec9a264fecac3abd87aea439ea; 6725a88f88a7e922e91c45bf83d320487810c192 up to, but not including, e12b95680821b9880cd9992c0f3555389363604f; 6725a88f88a7e922e91c45bf83d320487810c192 up to, but not including, 031f196d1b1b6d5dfcb0533b431e3ab1750e6189; 5.97257070be70e19a9138f39009c1a26c83a8a7cfa, bec1bea2fa974e63f6059c33edde669c7894d0bc, a16394b5d661afec9a264fecac3abd87aea439ea, e12b95680821b9880cd9992c0f3555389363604f, 031f196d1b1b6d5dfcb0533b431e3ab1750e6189
LinuxLinux Kernel5.9 up to, but not including, 5.10.176; 5.11 up to, but not including, 5.15.104; 5.16 up to, but not including, 6.1.21; 6.2 up to, but not including, 6.2.85.10.176, 5.15.104, 6.1.21, 6.2.8

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: drm/amd/display: fix shift-out-of-bounds in CalculateVMAndRowBytes [WHY] When PTEBufferSizeInRequests is zero, UBSAN reports the following warning because dml_log2 returns an unexpected negative value: shift exponent 4294966273 is too large for 32-bit type 'int' [HOW] In the case PTEBufferSizeInRequests is zero, skip the dml_log2() and assign the result directly.

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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