Path Traversal in Facebook Hhvm
CVE-2019-3556
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.
Vulnerability class: Path Traversal (Directory Traversal)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H.
EPSS exploit prediction
EPSS: 0.018 (77.5th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 77th percentile — 77.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.018 · newest: 0.018 · change: 0.000
Affected products
- Facebook Hhvm — versions 4.83.1, 4.83.0, 4.82.1
Weakness classification (CWE)
References
- hhvm.com/blog/2020/11/12/security-update.html (Vendor Advisory)
- github.com/facebook/hhvm/commit/abe0b29e4d3a610f9bc920b8be4ad8403364c2d4 (Patch, Third Party Advisory)
- www.facebook.com/security/advisories/cve-2019-3556 (Broken Link)
Frequently asked questions
- What is CVE-2019-3556?
- CVE-2019-3556 is a high-severity vulnerability in Facebook Hhvm, classified under Path Traversal. CVSS score: 8.1/10. Published 2021-10-26.
- How severe is CVE-2019-3556?
- High severity. CVSS v3 base score is 8.1 out of 10.