Composer before 2016-02-10 allows cache poisoning from other projects built on the same host. This results in attacker-controlled code entering a server-side build process. The issue occurs because of the way that dist packages are cached. The cache key is derived from the package name, the dist type, and certain other data from the package repository (which may simply be a commit hash, and thus can be found by an attacker). Versions through 1.0.0-alpha11 are affected, and 1.0.0 is unaffected.
CVE-2015-8371
HIGHNVD 8.88.8—Elevated
EchelonGraph scoreMEDIUM confidence
This high-severity CVE scores 8.8 under NVD CVSS v3. EPSS exploit probability: 0.7%, top 27% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
Triggered by: NVD CVSS baseline
Sources: epss, nvd
8.8
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
- High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 1%CVSS: 8.8Exploit: NoneExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 8.8
- EG Score
- 8.8(medium)
- EPSS
- 48.7%
- KEV
- Not listed
Published
September 21, 2023
Last Modified
November 21, 2024
References (8)
- cve@mitrehttps://flyingmana.de/blog_en/2016/02/14/composer_cache_injection_vulnerability_cve_2015_8371.html
- cve@mitrehttps://github.com/FriendsOfPHP/security-advisories/blob/e26be423c5bcfdb38478d2f92d1f928c15afb561/composer/composer/CVE-2015-8371.yaml
- cve@mitrehttps://github.com/composer/composer
- cve@mitrehttps://gitlab.com/gitlab-org/advisories-community/-/blob/main/packagist/composer/composer/CVE-2015-8371.yml
- af854a3a-2127-422b-91ae-364da2661108https://flyingmana.de/blog_en/2016/02/14/composer_cache_injection_vulnerability_cve_2015_8371.html
- af854a3a-2127-422b-91ae-364da2661108https://github.com/FriendsOfPHP/security-advisories/blob/e26be423c5bcfdb38478d2f92d1f928c15afb561/composer/composer/CVE-2015-8371.yaml
- af854a3a-2127-422b-91ae-364da2661108https://github.com/composer/composer
- af854a3a-2127-422b-91ae-364da2661108https://gitlab.com/gitlab-org/advisories-community/-/blob/main/packagist/composer/composer/CVE-2015-8371.yml
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Frequently asked(5)
What is CVE-2015-8371?
CVE-2015-8371 is a high vulnerability published on September 21, 2023. Composer before 2016-02-10 allows cache poisoning from other projects built on the same host. This results in attacker-controlled code entering a server-side build process. The issue occurs because of the way that dist packages are cached. The cache key is derived from the package name, the dist…
When was CVE-2015-8371 disclosed?
CVE-2015-8371 was first published in the National Vulnerability Database on September 21, 2023, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2015-8371 actively exploited?
CVE-2015-8371 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 48.7% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2015-8371?
CVE-2015-8371 has a CVSS v3 base score of 8.8 (NVD).
How do I remediate CVE-2015-8371?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2015-8371, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2015-8371
Is Your Infrastructure Affected by CVE-2015-8371?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.