CVE-2021-37704
CVE-2021-37704 is a medium-severity vulnerability in Phpfastcache with a CVSS 3.x base score of 5.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-668.
Key facts
- Severity: Medium (CVSS 3.x base score 5.4)
- CVSS v2: 4.0
- EPSS exploit prediction: 6% (93rd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-668
- Affected product: Phpfastcache
- Published:
- Last modified:
Description
PhpFastCache is a high-performance backend cache system (packagist package phpfastcache/phpfastcache). In versions before 6.1.5, 7.1.2, and 8.0.7 the `phpinfo()` can be exposed if the `/vendor` is not protected from public access. This is a rare situation today since the vendor directory is often located outside the web directory or protected via server rule (.htaccess, etc). Only the v6, v7 and v8 will be patched respectively in 8.0.7, 7.1.2, 6.1.5. Older versions such as v5, v4 are not longer supported and will **NOT** be patched. As a workaround, protect the `/vendor` directory from public access.
Frequently asked questions
- What is CVE-2021-37704?
- PhpFastCache is a high-performance backend cache system (packagist package phpfastcache/phpfastcache). In versions before 6.1.5, 7.1.2, and 8.0.7 the `phpinfo()` can be exposed if the `/vendor` is not protected from public access. This is a rare situation today since the vendor directory is often located outside the web directory or protected via server rule (.htaccess, etc). Only the v6, v7 and v8 will be patched respectively in 8.0.7, 7.1.2, 6.1.5. Older versions such as v5, v4 are not longer supported and will **NOT** be patched. As a workaround, protect the `/vendor` directory from public access.
- How severe is CVE-2021-37704?
- CVE-2021-37704 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability low.
- Is CVE-2021-37704 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-37704?
- CVE-2021-37704 affects Phpfastcache. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-37704?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2021-37704 published?
- CVE-2021-37704 was published on 2021-08-12 and last updated on 2026-06-17.
References
- https://github.com/PHPSocialNetwork/phpfastcache/blob/master/CHANGELOG.md#807
- https://github.com/PHPSocialNetwork/phpfastcache/commit/41a77d0d8f126dbd6fbedcd9e6a82e86cdaafa51
- https://github.com/PHPSocialNetwork/phpfastcache/pull/813
- https://github.com/PHPSocialNetwork/phpfastcache/pull/814
- https://github.com/PHPSocialNetwork/phpfastcache/pull/815
- https://github.com/PHPSocialNetwork/phpfastcache/security/advisories/GHSA-cvh5-p6r6-g2qc
- https://github.com/flextype/flextype/issues/567
- https://packagist.org/packages/phpfastcache/phpfastcache
Affected products (1)
- cpe:2.3:a:phpfastcache:phpfastcache:*:*:*:*:*:*:*:*
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