A vulnerability was found in PHP EXIF extension is parsing EXIF information from an image, e.g. via exif_read_data() function, in PHP versions 7.2.x below 7.2.26, 7.3.x below 7.3.13 and 7.4.0 it is possible to supply it with data what will cause it to read past the allocated buffer. This may lead to information disclosure or crash.
Created php tracking bugs for this issue:
Affects: fedora-all [bug 1786571]
Upstream commit for this bug:
There's an issue with PHP's EXIF module during a EXIF tag processing. When processing the Maker Note tag exif module fails to validate the data lenght, triggering an out of bounds read on a heap allocated value.
The out of bounds happens when exif_process_IFD_in_MAKERNOTE() function calls strncmp() to compare the Maker Note's id string. An attacker may leverage this by crafting a speciall EXIF section, leading to information disclousure and possible DoS.
This flaw has Low impact regarding Confidentiality as the attack has no control over the information which may be leaked and only a small chunck of heap data will be exposed.