How severe is CVE-2026-39087?

CVE-2026-39087 has a CVSS 3.x base score of 6.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2026-39087 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (19th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-39087?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-39087 have an EU (EUVD) identifier?

Yes. CVE-2026-39087 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-25232.

When was CVE-2026-39087 published?

CVE-2026-39087 was published on 2026-04-23 and last updated on 2026-07-04.

CVE-2026-39087

CVE-2026-39087 is a medium-severity vulnerability with a CVSS 3.x base score of 6.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-777.

Key facts

Severity: Medium (CVSS 3.x base score 6.4)
EPSS exploit prediction: 0% (19th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-25232
Weakness: CWE-777
Published: 2026-04-23
Last modified: 2026-07-04

Description

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

Frequently asked questions

What is CVE-2026-39087?: ntfy before 2.22.0 allows SSRF because of an unanchored regular expression for web push endpoint URLs.
How severe is CVE-2026-39087?: CVE-2026-39087 has a CVSS 3.x base score of 6.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2026-39087 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (19th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-39087?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-39087 have an EU (EUVD) identifier?: Yes. CVE-2026-39087 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-25232.
When was CVE-2026-39087 published?: CVE-2026-39087 was published on 2026-04-23 and last updated on 2026-07-04.

References

EU advisories (EUVD)

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