What is CVE-2020-23563?

CVE-2020-23563 is a medium-severity vulnerability in Irfanview, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 5.5/10. Published 2022-07-18.

How severe is CVE-2020-23563?

Medium severity. CVSS v3 base score is 5.5 out of 10.

Is CVE-2020-23563 known to be exploited?

2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Buffer overflow in Irfanview

CVE-2020-23563

IrfanView 4.54 allows a user-mode write access violation starting at FORMATS!ShowPlugInSaveOptions_W+0x0000000000002cba.

Vulnerability class: Buffer Overflow

Published 2022-07-18 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.003 (23.3th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 23rd percentile — 23.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Irfanview — versions 4.54

Weakness classification (CWE)

CWE-119 — Improper Restriction of Operations within the Bounds of a Memory Buffer

Public proof-of-concept exploits

References

www.irfanview.com/plugins.htm (Product)
github.com/nhiephon/Research (Third Party Advisory)

Frequently asked questions

What is CVE-2020-23563?: CVE-2020-23563 is a medium-severity vulnerability in Irfanview, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 5.5/10. Published 2022-07-18.
How severe is CVE-2020-23563?: Medium severity. CVSS v3 base score is 5.5 out of 10.
Is CVE-2020-23563 known to be exploited?: 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.