CVE-2026-110839

HIGH 7.1 PoC AVAILABLE

Published 2026-10-14 · Last modified 2026-10-15

FreeRDP 3.3.0 before 3.32.0, when built with WINPR_UTILS_IMAGE_JPEG=ON, has a heap-based out-of-bounds write in winpr_convert_from_jpeg because grayscale JPEG buffers are sized from one input component rather than three BGR output components. A malicious RDP server can offer a grayscale JPEG via clipboard redirection, corrupting client memory and crashing it when the item is pasted as CF_DIB bitmap data.

EXPLOIT AVAILABLE

Public exploit or PoC code exists. Modeled probability is still low, but the barrier to attack is reduced — watch closely.

Exploitation likelihood

0.2%chance of exploitation in 30 days · 12th percentile

○ In CISA KEV ● Public exploit / PoC

Impact if exploited

7.1CVSS 4.0 · HIGH

ConfidentialityNone
IntegrityLow
AvailabilityHigh

What an attacker needs

✓Access: Reachable over the network — no local access needed
✓Privileges: No account or privileges required
⚠User interaction: Succeeds with passive user activity
✓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-99p4-8j24-wvj4
github-search Search GitHub for public PoC repos

Test against your own equipment

curl -s https://vulnpedia.com/cve/CVE-2026-110839/poc.jsonMachine-readable PoC index for this CVE (for automation).

Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-110839/poc.json

Affected

Vendors Freerdp

Products Freerdp

Weakness (CWE)

CWE-787: Out-of-bounds Write

CVSS vector

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

All CVSS metrics

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

References

Exploits & PoC

https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-99p4-8j24-wvj4 vendor-advisoryexploit

Advisories

https://www.vulncheck.com/advisories/freerdp-3.3.0-before-3.32.0-heap-out-of-bounds-write-via-grayscale-jpeg-clipboard-data third-party-advisory

Sources: NVD · CVE.org · EPSS