HOMEVULNERABILITIESCVE-2023-43655
HIGH

CVE-2023-43655

CWE-74Published: September 29, 2023· Updated: Jun 17, 2026

8.8
CVSS v3.1

Official Description

Composer is a dependency manager for PHP. Users publishing a composer.phar to a public web-accessible server where the composer.phar can be executed as a php file may be subject to a remote code execution vulnerability if PHP also has `register_argc_argv` enabled in php.ini. Versions 2.6.4, 2.2.22 and 1.10.27 patch this vulnerability. Users are advised to upgrade. Users unable to upgrade should make sure `register_argc_argv` is disabled in php.ini, and avoid publishing composer.phar to the web as this is not best practice.

NVD Source

Technical Analysis

CVE-2023-43655 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 8.8.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.Low
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected Vendors & Products

Debian1 product(s)
debian linux
Fedora1 product(s)
fedora
getcomposer1 product(s)
composer
Source: NVD CPE · 4 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
External links open in a new tab. Always verify in a controlled environment before use.

Official Patches & Advisories

PATCHhttps://github.com/composer/composer/commit/4fce14795aba98e40b6c4f5047305aba17a6120d
PATCHhttps://github.com/composer/composer/commit/955a48e6319c8962e5cd421b07c00ab3c728968c
PATCHhttps://github.com/composer/composer/commit/95e091c921037b7b6564942845e7b738f6b95c9c
PATCHhttps://github.com/composer/composer/commit/4fce14795aba98e40b6c4f5047305aba17a6120d
PATCHhttps://github.com/composer/composer/commit/955a48e6319c8962e5cd421b07c00ab3c728968c
PATCHhttps://github.com/composer/composer/commit/95e091c921037b7b6564942845e7b738f6b95c9c
ADVISORYhttps://github.com/composer/composer/security/advisories/GHSA-jm6m-4632-36hf
ADVISORYhttps://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/66H2WKFUO255T3BZTL72TNYJYH2XM5FG/
ADVISORYhttps://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/7AWYAUZNH565NWPIKGEIYBWHYNM5JGAE/
ADVISORYhttps://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/KFOPGPW2KS37O3KJWBRGTUWHTXCQXBS2/
ADVISORYhttps://github.com/composer/composer/security/advisories/GHSA-jm6m-4632-36hf
ADVISORYhttps://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/66H2WKFUO255T3BZTL72TNYJYH2XM5FG/
ADVISORYhttps://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/7AWYAUZNH565NWPIKGEIYBWHYNM5JGAE/
ADVISORYhttps://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/KFOPGPW2KS37O3KJWBRGTUWHTXCQXBS2/

All References (16)

→
https://github.com/composer/composer/commit/4fce14795aba98e40b6c4f5047305aba17a6120dPatch
→
https://github.com/composer/composer/commit/955a48e6319c8962e5cd421b07c00ab3c728968cPatch
→
https://github.com/composer/composer/commit/95e091c921037b7b6564942845e7b738f6b95c9cPatch
→
https://github.com/composer/composer/security/advisories/GHSA-jm6m-4632-36hfVendor Advisory
→
https://lists.debian.org/debian-lts-announce/2024/03/msg00030.htmlMailing List
→
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/66H2WKFUO255T3BZTL72TNYJYH2XM5FG/Mailing List · Third Party Advisory
→
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/7AWYAUZNH565NWPIKGEIYBWHYNM5JGAE/Mailing List · Third Party Advisory
→
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/KFOPGPW2KS37O3KJWBRGTUWHTXCQXBS2/Mailing List · Third Party Advisory
→
https://github.com/composer/composer/commit/4fce14795aba98e40b6c4f5047305aba17a6120dPatch
→
https://github.com/composer/composer/commit/955a48e6319c8962e5cd421b07c00ab3c728968cPatch
→
https://github.com/composer/composer/commit/95e091c921037b7b6564942845e7b738f6b95c9cPatch
→
https://github.com/composer/composer/security/advisories/GHSA-jm6m-4632-36hfVendor Advisory
→
https://lists.debian.org/debian-lts-announce/2024/03/msg00030.htmlMailing List
→
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/66H2WKFUO255T3BZTL72TNYJYH2XM5FG/Mailing List · Third Party Advisory
→
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/7AWYAUZNH565NWPIKGEIYBWHYNM5JGAE/Mailing List · Third Party Advisory

Quick Facts

CVE IDCVE-2023-43655
CVSS Score8.8 / 10
SeverityHIGH
WeaknessCWE-74
CISA KEVNo
Affected3 vendor(s)
PublishedSep 29, 2023

Related CVEs (CWE-74)

CVE-2026-44182
10.0
CVE-2026-4963
10.0
CVE-2023-30547
10.0
CVE-2024-38366
10.0
CVE-2014-8423
10.0
CVE-2020-26282
10.0

Recommended Actions

  • →Apply vendor patches immediately
  • →Monitor CVE-2023-43655 in threat intel feeds
  • →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWatch. CVE data is provided under the NVD usage policy.
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