CVE-2017-9218

Vulnerability

In Freeware Advanced Audio Decoder 2 (FAAD2) version 2.7, the function mp4ff_read_stsd in common/mp4ff/mp4atom.c performs an invalid memory read when processing a specially crafted MP4 file. This occurs because the function does not properly validate input data from the MP4 container, allowing a remote attacker to trigger a segmentation fault. The vulnerability is reachable when the faad decoder attempts to parse a malformed stsd atom in an MP4 file.

Exploitation

An attacker can exploit this vulnerability by providing a crafted MP4 file to the faad decoder. No authentication or special privileges are required; the victim only needs to open the malicious file using FAAD2. The crash occurs during the parsing phase, as demonstrated by the ASAN report showing a segfault at a null-like address ([1]).

Impact

Successful exploitation causes a denial of service (DoS) due to an invalid memory read, resulting in a crash of the application. There is no indication of code execution or data exfiltration; the impact is limited to availability degradation [1].

Mitigation

As of the available references, no official patch has been released for FAAD2 2.7. Users should avoid processing untrusted MP4 files with the affected version or consider using alternative decoders until a fix becomes available. The issue is not listed in CISA's Known Exploited Vulnerabilities catalog [1].