CVE-2019-11049

MediumCVSS 6.5

Published: 23/12/2019(UTC)Updated: 17/08/2026(UTC)Translated: 17/08/2026(UTC)NVD NIST

Exploitation Probability (EPSS)

Very high risk

4.22%

90th percentile - higher than 90% of all known CVEs

Summary

In PHP versions 7.3.x below 7.3.13 and 7.4.0 on Windows, when supplying custom headers to the mail() function, if the header is supplied in lowercase, it can result in double-freeing certain memory locations.

Risk Assessment

Double-free can lead to application crashes or potentially arbitrary code execution.

Recommendation

Upgrade PHP to version 7.3.13 or later (or 7.4.1+).

Original NVD description (English source)

In PHP versions 7.3.x below 7.3.13 and 7.4.0 on Windows, when supplying custom headers to mail() function, due to mistake introduced in commit 78f4b4a2dcf92ddbccea1bb95f8390a18ac3342e, if the header is supplied in lowercase, this can result in double-freeing certain memory locations.