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Fencer Vulns
high 8.8

CVE-2020-24994 json

Stack overflow in the parse_tag function in libass/ass_parse.c in libass before 0.15.0 allows remote attackers to cause a denial of service…

published 2021-03-23 5 y ago modified 2026-07-25 3 mo ago also EUVD-2020-17694 , JLSEC-2026-154

cvss
8.8
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
2.6%
EPSS 2.6% chance of exploitation in 30 days, percentile 85%
public exploits
0
none known

Summary

Stack overflow in the parse_tag function in libass/ass_parse.c in libass before 0.15.0 allows remote attackers to cause a denial of service or remote code execution via a crafted file.

Patch / fix

  • julia libass_jll 0.15.1+0
  • libass_project libass 0.15.0
  • libass Debian 14, Debian 13, Debian 12 1:0.15.0-1

debian advisories DEBIAN-CVE-2020-24994

  • libass Ubuntu Pro 14.04 LTS 0.10.1-3ubuntu1+esm2
  • libass Ubuntu Pro 16.04 LTS 0.13.1-1ubuntu0.1~esm2
  • libass Ubuntu Pro 18.04 LTS 1:0.14.0-1ubuntu0.1~esm1
  • libass Ubuntu Pro 20.04 LTS 1:0.14.0-2ubuntu0.1~esm1

ubuntu advisories UBUNTU-CVE-2020-24994

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • libass SLE Module for Desktop Applications 15 SP3, SLE Module for Desktop Applications 15 SP2 0.14.0-3.6.1

suse advisories SUSE-SU-2021:1664-1

  • libass openSUSE Leap 15.3 0.14.0-3.6.1
  • libass openSUSE Leap 15.2 0.14.0-lp152.4.6.1

opensuse advisories openSUSE-SU-2021:1664-1openSUSE-SU-2021:0773-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2020-24994 updated cvss 7.4

libass: Stack overflow in the parse_tag function in libass/ass_parse.c

  • Red Hat All currently supported Red Hat products
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

2.65% chance of exploitation in the next 30 days, higher than 85% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
NVD 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
NVD 2.0 6.8 AV:N/AC:M/Au:N/C:P/I:P/A:P
OSV 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Affected packages

ecosystem package affected fixed in
julia libass_jll
<0.15.1+0
0.15.1+0

Classification

Weakness
  • CWE-770 Allocation of Resources Without Limits or Throttling

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.