{"cve":"CVE-2019-3556","nvd":{"published":"2021-10-26T20:15:07.603","modified":"2026-06-17T02:35:13.310","status":"Modified","description":"HHVM supports the use of an \"admin\" server which accepts administrative requests over HTTP. One of those request handlers, dump-pcre-cache, can be used to output cached regular expressions from the current execution context into a file. The handler takes a parameter which specifies where on the filesystem to write this data. The parameter is not validated, allowing a malicious user to overwrite arbitrary files where the user running HHVM has write access. This issue affects HHVM versions prior to 4.56.2, all versions between 4.57.0 and 4.78.0, as well as 4.79.0, 4.80.0, 4.81.0, 4.82.0, and 4.83.0.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H","score":8.1},"cwes":["CWE-22"],"references":["https://github.com/facebook/hhvm/commit/abe0b29e4d3a610f9bc920b8be4ad8403364c2d4","https://hhvm.com/blog/2020/11/12/security-update.html","https://www.facebook.com/security/advisories/cve-2019-3556","https://github.com/facebook/hhvm/commit/abe0b29e4d3a610f9bc920b8be4ad8403364c2d4","https://hhvm.com/blog/2020/11/12/security-update.html"],"products":["facebook:hhvm"],"source":"nvd","synced_at":"2026-10-19T21:24:39.218183596+00:00"},"epss":{"cve":"CVE-2019-3556","score":0.01789,"percentile":0.78349,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}