CVE-2018-20199

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.1% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2018-12-18 · updated 2026-06-17
Weakness: CWE-476

Description

A NULL pointer dereference was discovered in ifilter_bank of libfaad/filtbank.c in Freeware Advanced Audio Decoder 2 (FAAD2) 2.8.8. The vulnerability causes a segmentation fault and application crash, which leads to denial of service because adding to windowed output is mishandled in the ONLY_LONG_SEQUENCE case.

Affected products

Audiocoding Freeware Advanced Audio Decoder 2: before 2.9.0 — fixed in 2.9.0
Debian Linux: 8.0, 9.0, 10.0

How to fix

Upgrade to a fixed version: Audiocoding Freeware Advanced Audio Decoder 2 2.9.0. Check the vendor advisory for mitigations.

References

https://github.com/knik0/faad2/issues/24
https://lists.debian.org/debian-lts-announce/2019/08/msg00033.html
https://lists.debian.org/debian-lts-announce/2021/10/msg00020.html
https://security.gentoo.org/glsa/202006-17
https://www.debian.org/security/2022/dsa-5109
https://github.com/knik0/faad2/issues/24
https://lists.debian.org/debian-lts-announce/2019/08/msg00033.html
https://lists.debian.org/debian-lts-announce/2021/10/msg00020.html
https://security.gentoo.org/glsa/202006-17
https://www.debian.org/security/2022/dsa-5109

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