CVE-2026-91948

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 ImpacttotalSuccessful exploitation gives total 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

0.59% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 47.9% of scored records. A rank, not a probability.

NVD base score

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

NVD CVSS vector

CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:H/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

Deferred. NVD last modified this record on 2026-09-17.

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

2026-09-15 15:18Z1 MO AGO

Last updated

2026-09-17 11:59Z1 MO AGO

Reserved

2026-09-15

Assigning CNA

VulnCheck

Record state

PUBLISHED

Severity

High (CVSS 7.7)

CNA CVSS vector

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

Weaknesses

• CWE-191Integer Underflow (Wrap or Wraparound)Base
• CWE-124Buffer Underwrite ('Buffer Underflow')Base

Data version

5.2

Document digest

913cfbdefce8eefc40a2fbc612f840cf6a0847441781755095093246987dac93

• github.comGitHub Security Advisory (GHSA-9jcm-x588-gh26)https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-9jcm-x588-gh26vendor-advisory
• github.comPatch Commithttps://github.com/FreeRDP/FreeRDP/commit/40d9202cd95551600c07437ce6bd5ecd7d31e57bpatch
• www.vulncheck.comVulnCheck Advisory: FreeRDP before 3.31.0 Out-of-bounds Write via SHOW_PROTOCOLhttps://www.vulncheck.com/advisories/freerdp-before-3.31.0-out-of-bounds-write-via-show-protocolthird-party-advisory