CVE-2020-14153

Vulnerability

In IJG JPEG (libjpeg) versions 8 through 9c, the file jdhuff.c contains an out-of-bounds array read vulnerability related to certain table pointers [1]. This flaw occurs during Huffman decoding when processing specially crafted JPEG files that trigger improper table pointer initialization, leading to a read beyond the allocated buffer boundaries.

Exploitation

An attacker must supply a malicious JPEG image to an application or library using a vulnerable version of libjpeg. No authentication is required if the image is processed automatically (e.g., via web upload, email attachment, or image viewer). The attacker needs no prior write access or special network position other than the ability to deliver the crafted file to the target system.

Impact

Successful exploitation results in an out-of-bounds memory read, which may lead to information disclosure (leaking sensitive heap data) or cause the application to crash (denial of service). The attacker does not achieve code execution via this specific read; the primary risks are confidentiality and availability [1].

Mitigation

The vulnerability is fixed in libjpeg version 9d, which was released after the report. Upgrading to libjpeg 9d or later resolves the issue [1]. Users of older versions (8 through 9c) should update immediately. No workaround is available besides applying the vendor patch or upgrading.