CyberSecBulletin
CVE-2024-11233NVD status: Modified

PHP: Out-of-bounds Write

CVE-2024-11233 is a high-severity out-of-bounds write vulnerability in PHP from PHP Group, with a CVSS 3.1 base score of 8.2 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions 8.1.31, 8.2.26, 8.3.14 as the first without the flaw, so updating PHP to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 1.61% chance of exploitation within 30 days, higher than 76% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update PHP to 8.1.31 or 8.2.26 or 8.3.14, whichever matches your release line, or a later version.
  2. Read the advisory on github.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
PHP GroupPHP8.1.* up to, but not including, 8.1.31; 8.2.* up to, but not including, 8.2.26; 8.3.* up to, but not including, 8.3.14; 8.1.0 up to, but not including, 8.1.31; 8.2.0 up to, but not including, 8.2.26; 8.3.0 up to, but not including, 8.3.148.1.31, 8.2.26, 8.3.14

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
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
LowSome restricted data can be read.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.14.8MediumCNA (php.net)
CVSS 3.18.2HighNVD

Official description

In PHP versions 8.1.* before 8.1.31, 8.2.* before 8.2.26, 8.3.* before 8.3.14, due to an error in convert.quoted-printable-decode filter certain data can lead to buffer overread by one byte, which can in certain circumstances lead to crashes or disclose content of other memory areas.

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

Other vulnerabilities in PHP

All PHP vulnerabilities

Recent Out-of-bounds Write vulnerabilities

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