What is CVE-2025-45663?

CVE-2025-45663 is a medium-severity vulnerability in Netsurf-Browser Netsurf, classified under CWE-244. CVSS score: 6.5/10. Published 2025-11-03.

How severe is CVE-2025-45663?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Vulnerability in Netsurf-Browser Netsurf

CVE-2025-45663

An issue in NetSurf v3.11 causes the application to read uninitialized heap memory when creating a dom_event structure.

Published 2025-11-03 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L.

EPSS exploit prediction

EPSS: 0.004 (29.4th percentile), scored 2026-10-20.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 29th percentile — 29.4% 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: 0.004 · change: +0.000

Affected products

Netsurf-Browser Netsurf — versions 3.11

Weakness classification (CWE)

CWE-244

References

github.com/Fysac/netsurf-disclosure/tree/main/CVE-2025-45663 (Exploit, Third Party Advisory)
www.netsurf-browser.org/ (Product)

Frequently asked questions

What is CVE-2025-45663?: CVE-2025-45663 is a medium-severity vulnerability in Netsurf-Browser Netsurf, classified under CWE-244. CVSS score: 6.5/10. Published 2025-11-03.
How severe is CVE-2025-45663?: Medium severity. CVSS v3 base score is 6.5 out of 10.