What is CVE-2020-23109?

CVE-2020-23109 is a high-severity vulnerability in Struktur Libheif, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 8.1/10. Published 2021-11-03.

How severe is CVE-2020-23109?

High severity. CVSS v3 base score is 8.1 out of 10.

Buffer overflow in Struktur Libheif

CVE-2020-23109

Buffer overflow vulnerability in function convert_colorspace in heif_colorconversion.cc in libheif v1.6.2, allows attackers to cause a denial of service and disclose sensitive information, via a crafted HEIF file.

Vulnerability class: Buffer Overflow

Published 2021-11-03 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H.

EPSS exploit prediction

EPSS: 0.013 (71.2th percentile), scored 2026-10-23.

Low probability of exploitation in the next 30 days, but still tracked. 71st percentile — 71.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.013 · newest: 0.013 · change: 0.000

Affected products

Struktur Libheif — versions 1.6.2

Weakness classification (CWE)

CWE-120 — Buffer Copy without Checking Size of Input (Classic Buffer Overflow)

References

github.com/strukturag/libheif/issues/207 (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2020-23109?: CVE-2020-23109 is a high-severity vulnerability in Struktur Libheif, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 8.1/10. Published 2021-11-03.
How severe is CVE-2020-23109?: High severity. CVSS v3 base score is 8.1 out of 10.