CVE-2026-18427

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.
• AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
• 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

0.65% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 50.9% of scored records. A rank, not a probability.

NVD base score

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

NVD CVSS vector

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

NVD analysis status

Analyzed. NVD last modified this record on 2026-09-04.

Red Hat severity

Important. Red Hat's rating for its own products, not a CVSS rating.

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

2026-08-06 14:52Z2 MO AGO

Last updated

2026-08-06 15:44Z2 MO AGO

Reserved

2026-07-30

Assigning CNA

openjs

Record state

PUBLISHED

Severity

High (CVSS 7.5)

CNA CVSS vector

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

Weaknesses

• CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')Base
• CWE-436Interpretation ConflictClass
• CWE-41Improper Resolution of Path EquivalenceBase

Data version

5.2

Document digest

c84fbfb5a7827482b5b8b90a1bc221fe24a103172f5693261c636c61921551b5

• github.comhttps://github.com/fastify/fastify-static/security/advisories/GHSA-423g-23ch-w7c6
• cna.openjsf.orghttps://cna.openjsf.org/security-advisories.html