CVE-2026-91945

HIGH 7.1 PoC AVAILABLE ALL-YEARS

Published 2026-09-15 · Last modified 2026-09-15 · VulnCheck · NVD: Analyzed

FreeRDP versions before 3.31.0 contain an out-of-bounds read vulnerability in smartcard response decoders that fail to validate ATR length fields against fixed inline arrays. Authenticated RDP clients can send oversized ATR lengths in PAKID_CORE_DEVICE_IOCOMPLETION responses to trigger reads past stack or heap objects, causing process termination.

EXPLOIT AVAILABLE

Public exploit or PoC code exists. The barrier to attack is reduced — watch closely.

Exploitation likelihood

0.6%chance of exploitation in 30 days · 47th percentile

○ In CISA KEV● Public exploit / PoC◆ SSVC: exploitation poc, automatable no

Impact if exploited

7.1CVSS 4.0 · HIGH · CNA

ConfidentialityNone
IntegrityNone
AvailabilityHigh

What an attacker needs

✓Access: Reachable over the network — no local access needed
⚠Privileges: Requires a low-privilege account
✓User interaction: No user interaction needed
✓Complexity: No special conditions — reliably repeatable
✓Requirements: No special attack requirements

✓ lowers the bar for an attacker · ⚠ raises it

Proof of concept & exploit code

reference https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-q65v-4w7q-hx3r
github-search https://github.com/search?q=%22CVE-2026-91945%22&type=repositories

Test against your own equipment

curl -s https://vulnpedia.com/cve/CVE-2026-91945/poc.jsonMachine-readable PoC index for this CVE (for automation).

For defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-91945/poc.json

Affected

Vendors Freerdp

Products Freerdp

Weakness (CWE)

CWE-125: Out-of-bounds Read

CVSS vector

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

Known Affected Software Configurations

Vendor	Product	Version range
Freerdp	Freerdp	≥ 3.28.0 and < 3.31.0

All CVSS metrics

HIGH 7.1 v4.0 · CNA Primary
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
MEDIUM 6.5 v3.1 · CNA Primary
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
HIGH 7.1 v4.0 · NVD Secondary
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/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
MEDIUM 6.5 v3.1 · NVD Primary
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

References

Sources: NVD · CVE.org · EPSS