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Public proof of conceptFix available

CVE-2024-2757

A public proof of concept exists; no exploitation attested.

  • Published2024-04-29
  • Fixed in8.3.5
  • WeaknessCWE-400

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

In PHP 8.3.* before 8.3.5, function mb_encode_mimeheader() runs endlessly for some inputs that contain long strings of non-space characters followed by a space. This could lead to a potential DoS attack if a hostile user sends data to an application that uses this function.

Timeline

dates in UTC
  1. 2024-04-2904:15CVE publishedNVD

Versions per branch

NVD · OSV · CISA-ADP
PHP
BranchAffectedFixed in
8.3≥ 8.3.0, < 8.3.58.3.5
Php group php
BranchAffectedFixed in
8.3= 8.3no fix published

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Products declared by the CNA1 product

As php, the CNA that assigned this CVE, declared them in the CVE record; versions as written.

  • PHP Group PHPother versions: not affected
    Affected
    • ≥ 8.3.*, < 8.3.5fixed in 8.3.5semver

Source: the CNA record (CVE Program), © The MITRE Corporation,CVE Terms of UseCVE recordupdated 2024-04-29

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

  • phpCleanStartall versions · fixed in 8.3.5-r0and 3 other packages
  • phpAzure Linux:3all versions · fixed in 8.3.6-1
  • php8openSUSE:Tumbleweedall versions · fixed in 8.3.6-1.1
  • php8.3Ubuntu:24.04:LTSall versions · fixed in 8.3.6-0maysync1
  • php83Alpine:v3.24all versions · fixed in 8.3.5-r0
  • php83Alpine:v3.23all versions · fixed in 8.3.5-r0
  • php83Alpine:v3.22all versions · fixed in 8.3.5-r0
  • php83Alpine:v3.21all versions · fixed in 8.3.5-r0

3 more package ranges on OSV.dev

Vendor advisories

  • CVE-2024-2757 Red Hat Product Security

    php: mb_encode_mimeheader runs endlessly for some inputs

Full record on NVD

Fix

  1. Update PHP to 8.3.5
  2. Workaround from the vendor Red Hat Product Security CVE-2024-2757 · 299 productsMitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.

Advisories and patches

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof of concept
Metasploit modules
none listed
Metasploit Framework

Sources

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published
2024-04-29
Last Modified
2026-06-17
NVD status
Modified
GitHub Advisory
GHSA-fjp9-9hwx-59fq

Frequently asked questions

What is CVE-2024-2757?

In PHP 8.3.* before 8.3.5, function mb_encode_mimeheader() runs endlessly for some inputs that contain long strings of non-space characters followed by a space. This could lead to a potential DoS attack if a hostile user sends data to an application that uses this function.

Is CVE-2024-2757 actively exploited?

A proof-of-concept exploit exists for CVE-2024-2757, but active exploitation has not been confirmed at this time.

What is the CVSS score for CVE-2024-2757?

CVE-2024-2757 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

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Sources for this record