CVE-2025-5020

Exploitation

Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.

SSVC decision

• ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
• AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
• Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.23% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 14.3% of scored records. A rank, not a probability.

NVD base score

4.3 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N

NVD analysis status

Modified. NVD last modified this record on 2026-10-05.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2025-05-21 17:18Z1 YR AGO

Last updated

2026-04-13 14:30Z6 MO AGO

Reserved

2025-05-21

Assigning CNA

mozilla

Record state

PUBLISHED

Severity

Medium (CVSS 4.3)

CNA CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N

Weaknesses

• CWE-939Improper Authorization in Handler for Custom URL SchemeBase

Data version

5.2

Document digest

410c0123feb2d81717c1e5b48635561445ad33dd82e7a4166eae78e3a049899e

• bugzilla.mozilla.orghttps://bugzilla.mozilla.org/show_bug.cgi?id=1951558
• www.mozilla.orghttps://www.mozilla.org/security/advisories/mfsa2025-39/