CVE-2026-93599

Exploitation

Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.

SSVC decision

• ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
• 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

0.34% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 27.9% of scored records. A rank, not a probability.

NVD base score

8.7 (CVSS v4.0), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

NVD analysis status

Awaiting Analysis. NVD last modified this record on 2026-09-22.

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

2026-09-18 13:20Z1 MO AGO

Last updated

2026-09-18 14:15Z1 MO AGO

Reserved

2026-09-18

Assigning CNA

VulnCheck

Record state

PUBLISHED

Severity

High (CVSS 8.7)

CNA CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Weaknesses

• CWE-191Integer Underflow (Wrap or Wraparound)Base
• CWE-125Out-of-bounds ReadBase

Data version

5.2

Document digest

b8916ede87071b84b727c45448c5a3567a43b634a3be49c90880c3d2f02e1ffe

• github.comGitHub Security Advisory (GHSA-82j2-j2ch-gfr8)https://github.com/rustls/webpki/security/advisories/GHSA-82j2-j2ch-gfr8vendor-advisory
• www.vulncheck.comVulnCheck Advisory: rustls-webpki before 0.103.13 Panic via empty BIT STRINGhttps://www.vulncheck.com/advisories/rustls-webpki-before-0.103.13-panic-via-empty-bit-stringthird-party-advisory