CVE-2020-23852

Vulnerability

A heap-based buffer overflow vulnerability exists in ffjpeg through 2020-07-02 in the jfif_decode(void *ctxt, BMP *pb) function at ffjpeg/src/jfif.c lines 544 and 545 [1]. The overflow occurs when indexing into the yuv_datbuf array without proper bounds checking, leading to out-of-bounds reads [1].

Exploitation

An attacker can exploit this vulnerability by providing a specially crafted JPEG image to the ffjpeg library [1]. No authentication or special network position is required; the attack can be executed remotely if the application processes user-supplied images [1].

Impact

Successful exploitation causes a denial of service (DoS) via application crash due to a heap-buffer-overflow read [1]. The crash results from accessing memory beyond the allocated buffer, as detected by AddressSanitizer [1].

Mitigation

As of the publication date, no official fix has been released for ffjpeg [1]. Users are advised to avoid processing untrusted JPEG images with ffjpeg or apply input validation if possible [1].