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Fencer Vulns
medium 5.4

CVE-2021-37704 json

Exposed phpinfo() in PhpFastCache

published 2021-08-12 5 y ago modified 2026-09-10 1 mo ago also GHSA-cvh5-p6r6-g2qc , EUVD-2021-1686

cvss
5.4
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
5.9%
EPSS 5.9% chance of exploitation in 30 days, percentile 93%
public exploits
0
none known, plus a Nuclei check

Summary

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.

Patch / fix

  • packagist phpfastcache/phpfastcache 6.1.5, 7.1.2, 8.0.7
  • phpfastcache phpfastcache 6.1.5, 7.1.2, 8.0.7

Exploit prediction

5.89% chance of exploitation in the next 30 days, higher than 93% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • Nuclei template phpfastcache - phpinfo Resource Exposure nuclei detection template
  • github.com https://github.com/flextype/flextype/issues/567 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 5.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:L
NVD 3.1 4.3 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
NVD 2.0 4.0 AV:N/AC:L/Au:S/C:P/I:N/A:N
GitHub 3.1 5.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:L

Affected packages

ecosystem package affected fixed in
packagist phpfastcache/phpfastcache
<6.1.5
>=7.0.0, <7.1.2
>=8.0.0, <8.0.7
6.1.5
7.1.2
8.0.7

Affected products

  • PHPSocialNetwork phpfastcache

Classification

Weakness
  • CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
  • CWE-668 Exposure of Resource to Wrong Sphere

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.