Medium severity · published Jul 8, 2026
CVE-2026-59946
Composer: Path traversal in package bin field lets dependencies chmod arbitrary host files
6.1
CVSS
0.1%
EPSS
No
On KEV
Description
Composer is a dependency Manager for the PHP language. Prior to 2.2.29 and 2.10.2, a Composer package bin entry containing .. path segments can resolve outside the package install directory and cause Composer's binary installation flow to chmod an existing host file to a world-readable and world-executable mode during composer install, update, or require. This issue is fixed in versions 2.2.29 and 2.10.2.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 3% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CO
composer · composer
>= 1.0, < 2.2.29; >= 2.3.0, < 2.10.2 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-59946
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-59946
github.com
https://github.com/composer/composer/commit/502c6c4f699802d9cf464728b3e8a95674f919a0
github.com
https://github.com/composer/composer/commit/c50b1efd13ebd73f6dca19b31424c5a02bf93cc1
github.com
https://github.com/composer/composer/releases/tag/2.10.2
github.com
https://github.com/composer/composer/releases/tag/2.2.29
github.com
https://github.com/composer/composer/security/advisories/GHSA-gjfg-22fp-rrxx
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