RCE in Ntfy

CVE-2026-39087

ntfy before 2.22.0 allows SSRF because of an unanchored regular expression for web push endpoint URLs.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.005 (40.2th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 40th percentile — 40.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-39087: held from 0.003 to 0.005.

EPSS over last 30 days · oldest: 0.003 · newest: 0.005 · change: +0.002

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-39087?
CVE-2026-39087 is a medium-severity vulnerability in Ntfy, classified under CWE-777. CVSS score: 6.4/10. Published 2026-04-23.
How severe is CVE-2026-39087?
Medium severity. CVSS v3 base score is 6.4 out of 10.