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Fencer Vulns
high 7.8

CVE-2020-36430 json

libass 0.15.x before 0.15.1 has a heap-based buffer overflow in decode_chars (called from decode_font and process_text) because the wrong i…

published 2021-07-20 5 y ago modified 2026-06-17 4 mo ago also EUVD-2020-23958

cvss
7.8
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
1.1%
EPSS 1.1% chance of exploitation in 30 days, percentile 65%
public exploits
0
none known

Summary

libass 0.15.x before 0.15.1 has a heap-based buffer overflow in decode_chars (called from decode_font and process_text) because the wrong integer data type is used for subtraction.

Patch / fix

  • libass_project libass 0.15.1
  • libass Debian 14, Debian 13, Debian 12 1:0.15.0-2

debian advisories DEBIAN-CVE-2020-36430

  • libass SLES for SAP 15 SP1, SLES for SAP 15, SLES 15-LTSS +12 more 0.14.0-3.9.1

suse advisories SUSE-SU-2021:2792-1

  • libass openSUSE Leap 15.2 0.14.0-lp152.4.9.1
  • libass openSUSE Leap 15.3 0.14.0-3.9.1

opensuse advisories openSUSE-SU-2021:1174-1openSUSE-SU-2021:2792-1

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-2020-36430 updated cvss 6.5

libass: heap-based buffer overflow in decode_chars because the wrong integer data type is used for subtraction

  • 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

1.08% chance of exploitation in the next 30 days, higher than 65% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
NVD 3.1 7.8 CVSS:3.1/AV:L/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

Classification

Weakness

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.