CyberSecBulletin
CVE-2023-52775NVD status: Modified

Linux: Out-of-bounds Write

Published Updated By the CyberSecBulletin desk

CVE-2023-52775 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 5ada292b5c504720a0acef8cae9acc62a694d19c, 90072af9efe8c7bd7d086709014ddd44cebd5e7c, 94a0ae698b4d5d5bb598e23228002a1491c50add 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 0.67% chance of exploitation within 30 days, higher than 53% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Linux to 5ada292b5c504720a0acef8cae9acc62a694d19c or 90072af9efe8c7bd7d086709014ddd44cebd5e7c or 94a0ae698b4d5d5bb598e23228002a1491c50add or 7234d2b5dffa5af77fd4e0deaebab509e130c6b1, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 5.10.203 or 5.15.141 or 6.1.65 or 6.6.4, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux0fb0b02bd6fd26cba38002be4a6bbcae2228fd44 up to, but not including, 5ada292b5c504720a0acef8cae9acc62a694d19c; 0fb0b02bd6fd26cba38002be4a6bbcae2228fd44 up to, but not including, 90072af9efe8c7bd7d086709014ddd44cebd5e7c; 0fb0b02bd6fd26cba38002be4a6bbcae2228fd44 up to, but not including, 94a0ae698b4d5d5bb598e23228002a1491c50add; 0fb0b02bd6fd26cba38002be4a6bbcae2228fd44 up to, but not including, 7234d2b5dffa5af77fd4e0deaebab509e130c6b1; 0fb0b02bd6fd26cba38002be4a6bbcae2228fd44 up to, but not including, e6d71b437abc2f249e3b6a1ae1a7228e09c6e563; 5.85ada292b5c504720a0acef8cae9acc62a694d19c, 90072af9efe8c7bd7d086709014ddd44cebd5e7c, 94a0ae698b4d5d5bb598e23228002a1491c50add, 7234d2b5dffa5af77fd4e0deaebab509e130c6b1, e6d71b437abc2f249e3b6a1ae1a7228e09c6e563
LinuxLinux Kernel5.8 up to, but not including, 5.10.203; 5.11 up to, but not including, 5.15.141; 5.16 up to, but not including, 6.1.65; 6.2 up to, but not including, 6.6.4; 6.75.10.203, 5.15.141, 6.1.65, 6.6.4

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.

Scoring systemScoreSeverityScored by
CVSS 3.18.2HighCNA
CVSS 3.17.8HighNVD

Official description

In the Linux kernel, the following vulnerability has been resolved: net/smc: avoid data corruption caused by decline We found a data corruption issue during testing of SMC-R on Redis applications. The benchmark has a low probability of reporting a strange error as shown below. "Error: Protocol error, got "\xe2" as reply type byte" Finally, we found that the retrieved error data was as follows: 0xE2 0xD4 0xC3 0xD9 0x04 0x00 0x2C 0x20 0xA6 0x56 0x00 0x16 0x3E 0x0C 0xCB 0x04 0x02 0x01 0x00 0x00 0x20 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0xE2 It is quite obvious that this is a SMC DECLINE message, which means that the applications received SMC protocol message. We found that this was caused by the following situations: client server ¦ clc proposal -------------> ¦ clc accept <------------- ¦ clc confirm -------------> wait llc confirm send llc confirm ¦failed llc confirm ¦ x------ (after 2s)timeout wait llc confirm rsp wait decline (after 1s) timeout (after 2s) timeout ¦ decline --------------> ¦ decline <-------------- As a result, a decline message was sent in the implementation, and this message was read from TCP by the already-fallback connection. This patch double the client timeout as 2x of the server value, With this simple change, the Decline messages should never cross or collide (during Confirm link timeout). This issue requires an immediate solution, since the protocol updates involve a more long-term solution.

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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