CVE-2019-3556

HIGH
8.1
CVSS Score
Published: October 26, 2021 at 08:05 PM UTC
Updated: June 17, 2026 at 02:35 AM UTC
1 product affected across 1 vendorHHVM

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Severity
HIGH8.1
Exploit prediction
EPSS 2%

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v ≥ 4.57.0v ≥ 4.79.0v ≥ 4.80.0v ≥ 4.81.0v ≥ 4.82.0v ≥ 4.83.0v < 4.56.24.57.0 ≤ v ≤ 4.78.04.57.04.79.04.80.04.81.04.82.04.83.0
Vendor states this is fixed in 4.56.2 (unaffected)
Vendor states this is fixed in 4.78.1 (unaffected)
Vendor states this is fixed in 4.79.1 (unaffected)
Vendor states this is fixed in 4.80.1 (unaffected)
Vendor states this is fixed in 4.81.1 (unaffected)
Vendor states this is fixed in 4.82.1 (unaffected)
Vendor states this is fixed in 4.83.1 (unaffected)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
HIGH
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-22

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