CVE-2026-91950 json
FreeRDP before 3.31.0 Out-of-Bounds Read via UINT32 Wraparound
published 2mo ago modified last mo. also EUVD-2026-78807 , GHSA-c5gr-hmqp-pwj4
Unreviewed: the maintainers' own advisory
Published by the maintainers on their GitHub repository FreeRDP/FreeRDP. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.
- cvss
- 6.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 34%
- public exploits
- 0
- none known
Summary
FreeRDP before 3.31.0 contains an out-of-bounds read vulnerability in the rdpdr_dump_packet function due to 32-bit unsigned integer wraparound in buffer bounds validation. A malicious RDP server can send a crafted RDPDR packet with computerNameLen set to 0xFFFFFFF0 to bypass bounds checks and trigger memory reads past the packet buffer, causing client crashes or heap disclosure in logs.
Patch / fix
- FreeRDP FreeRDP 3.31.0
- freerdp3 Debian 14 3.31.0+dfsg-1
debian advisories DEBIAN-CVE-2026-91950
- freerdp3 Ubuntu 24.04 LTS 3.31.0+dfsg-0ubuntu0.24.04.1
- freerdp3 Ubuntu 26.04 LTS 3.31.0+dfsg-0ubuntu0.26.04.1
ubuntu advisories UBUNTU-CVE-2026-91950
Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0
- freerdp RHEL 10.2 2:3.10.3-12.el10_2.14
- libwinpr RHEL 10.2 2:3.10.3-12.el10_2.14
- freerdp-libs RHEL 10.2 2:3.10.3-12.el10_2.14
- freerdp-server RHEL 10.2 2:3.10.3-12.el10_2.14
red hat advisories RHSA-2026:75570
- freerdp AlmaLinux 10 2:3.10.3-12.el10_2.14
- libwinpr AlmaLinux 10 2:3.10.3-12.el10_2.14
- freerdp-libs AlmaLinux 10 2:3.10.3-12.el10_2.14
- freerdp-server AlmaLinux 10 2:3.10.3-12.el10_2.14
almalinux advisories ALSA-2026:75570
- freerdp Rocky Linux 10 2:3.10.3-12.el10_2.14
rocky linux advisories RLSA-2026:75570
Is CVE-2026-91950 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerVendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
red hat product security vex CVE-2026-91950 updated cvss 7.1
FreeRDP: FreeRDP: Out-of-bounds read leads to denial of service or information disclosure
-
Red Hat Enterprise Linux 6 freerdp, freerdp-libs, freerdp-pluginsaffected: workaround, no fix planned “Out of support scope”
-
Red Hat Enterprise Linux 9 freerdp, libwinpr, freerdp-libsaffected: workaround, no fix available
-
Red Hat Enterprise Linux AppStream (v. 10) freerdp 3.32.2-1.el10_3, libwinpr 3.32.2-1.el10_3, freerdp 3.10.3-12.el10_2.14, freerdp-libs 3.32.2-1.el10_3, libwinpr 3.10.3-12.el10_2.14, freerdp-libs 3.10.3-12.el10_2.14 Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) freerdp-server 3.32.2-1.el10_3, freerdp-server 3.10.3-12.el10_2.14fixed: vendor fix RHSA-2026:75570
-
Red Hat Enterprise Linux 7 freerdp, libwinpr, freerdp-libs, freerdp-plugins Red Hat Enterprise Linux 8 freerdp, libwinpr, freerdp-libsnot affected: vulnerable code not present
Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- last mo.
Exploit prediction
0.40% chance of exploitation in the next 30 days, higher than 34% of all scored CVEs (FIRST EPSS, 2026-11-11).
Exploits and checks
- github.com https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-c5gr-hmqp-pwj4 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 7.1 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |
| CNA | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H |
| CNA | 4.0 | 7.1 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/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 | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H |
Affected products
- FreeRDP FreeRDP
Classification
- Weakness
-
- CWE-125 Out-of-bounds Read
References
-
github.com
/FreeRDP/FreeRDP/security/advisories/GHSA-c5gr-hmqp-pwj4
vendor-advisory, exploit, mitigation, advisory
-
vulncheck.com
/advisories/freerdp-before-3.31.0-out-of-bounds-read-via-uint32-wraparound
third-party-advisory
Sources
- CVE List CVE-2026-91950
- NVD CVE-2026-91950
- Maintainer advisory GHSA-c5gr-hmqp-pwj4
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
The maintainers of FreeRDP/FreeRDP published their own advisory on GitHub. Reviewed sources take precedence over it.