FreeRDP before 3.29.0 Out-of-bounds Read via Polygon async message-proxy
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-125 and the CVSS impact.
Summary
FreeRDP before 3.29.0 contains out-of-bounds read vulnerabilities in the async update message proxy for the PolygonSC and PolygonCB primary drawing orders. When AsyncUpdate is enabled (e.g., xfreerdp /async-update), update_message_PolygonSC() and update_message_PolygonCB() allocate a fresh points array but copy point data from the address of the order structure instead of from polygonSC->points / polygonCB->points, resulting in a client-side out-of-bounds read. A malicious or compromised RDP server sending crafted PolygonSC/PolygonCB update orders can trigger memory disclosure or a client crash.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA FreeRDP (FreeRDP) Fixed in 3.29.0
Red Hat 11 advisories
- RHSA-2026:71387 Released 2026-09-24 · Red Hat rating Importantfreerdp security update
- Red Hat CodeReady Linux Builder EUS (v.9.6) freerdp-devel-2:2.11.7-1.el9_6.13, libwinpr-devel-2:2.11.7-1.el9_6.13
- Red Hat Enterprise Linux AppStream EUS (v.9.6) freerdp-2:2.11.7-1.el9_6.13, freerdp-libs-2:2.11.7-1.el9_6.13, libwinpr-2:2.11.7-1.el9_6.13
- RHSA-2026:71390 Released 2026-09-24 · Red Hat rating Importantfreerdp security update
- Red Hat Enterprise Linux AppStream E4S (v.9.4) freerdp-2:2.11.2-1.el9_4.11, freerdp-libs-2:2.11.2-1.el9_4.11, libwinpr-2:2.11.2-1.el9_4.11
- RHSA-2026:71388 Released 2026-09-24 · Red Hat rating Importantfreerdp security update
- Red Hat Enterprise Linux AppStream E4S (v.9.2) freerdp-2:2.4.1-6.el9_2.12, freerdp-libs-2:2.4.1-6.el9_2.12, libwinpr-2:2.4.1-6.el9_2.12
Show 8 more Red Hat advisories
- RHSA-2026:68707 Released 2026-09-17 · Red Hat rating Importantfreerdp security update
- Red Hat Enterprise Linux Server (v. 7 ELS) freerdp-2.1.1-5.el7_9.12, freerdp-libs-2.1.1-5.el7_9.12, freerdp-libs-2.1.1-5.el7_9.12.ppc +2
- Red Hat Enterprise Linux Server Optional (v. 7 ELS) freerdp-devel-2.1.1-5.el7_9.12, freerdp-devel-2.1.1-5.el7_9.12.ppc, libwinpr-devel-2.1.1-5.el7_9.12 +1
- RHSA-2026:68706 Released 2026-09-17 · Red Hat rating Importantfreerdp security update
- Red Hat Enterprise Linux AppStream EUS (v. 10.0) freerdp-2:3.10.3-3.el10_0.16, freerdp-libs-2:3.10.3-3.el10_0.16, libwinpr-2:3.10.3-3.el10_0.16
- Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) freerdp-devel-2:3.10.3-3.el10_0.16, freerdp-server-2:3.10.3-3.el10_0.16, libwinpr-devel-2:3.10.3-3.el10_0.16
- RHSA-2026:66282 Released 2026-09-10 · Red Hat rating Importantfreerdp security update
- Red Hat Enterprise Linux AppStream E4S (v.8.8) freerdp-2:2.2.0-12.el8_8.11, freerdp-libs-2:2.2.0-12.el8_8.11, libwinpr-2:2.2.0-12.el8_8.11 +1
- Red Hat Enterprise Linux AppStream TUS (v.8.8) freerdp-2:2.2.0-12.el8_8.11, freerdp-libs-2:2.2.0-12.el8_8.11, libwinpr-2:2.2.0-12.el8_8.11 +1
- RHSA-2026:66281 Released 2026-09-10 · Red Hat rating Importantfreerdp security update
- Red Hat Enterprise Linux AppStream AUS (v.8.6) freerdp-2:2.2.0-7.el8_6.12, freerdp-libs-2:2.2.0-7.el8_6.12, libwinpr-2:2.2.0-7.el8_6.12 +1
- Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) freerdp-2:2.2.0-7.el8_6.12, freerdp-libs-2:2.2.0-7.el8_6.12, libwinpr-2:2.2.0-7.el8_6.12 +1
- RHSA-2026:65855 Released 2026-09-09 · Red Hat rating Importantfreerdp security update
- Red Hat Enterprise Linux AppStream AUS (v.8.4) freerdp-2:2.2.0-14.el8_4.3, freerdp-libs-2:2.2.0-14.el8_4.3, libwinpr-2:2.2.0-14.el8_4.3 +1
- Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) freerdp-2:2.2.0-14.el8_4.3, freerdp-libs-2:2.2.0-14.el8_4.3, libwinpr-2:2.2.0-14.el8_4.3 +1
- RHSA-2026:62571 Released 2026-09-02 · Red Hat rating Importantfreerdp security update
- Red Hat Enterprise Linux AppStream (v. 8) freerdp-2:2.11.7-12.el8_10, freerdp-libs-2:2.11.7-12.el8_10, libwinpr-2:2.11.7-12.el8_10 +1
- Red Hat Enterprise Linux CRB (v. 8) freerdp-devel-2:2.11.7-12.el8_10
- RHSA-2026:61378 Released 2026-08-31 · Red Hat rating Importantfreerdp security update
- Red Hat Enterprise Linux AppStream (v. 10) freerdp-2:3.10.3-12.el10_2.10, freerdp-libs-2:3.10.3-12.el10_2.10, libwinpr-2:3.10.3-12.el10_2.10
- Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) freerdp-devel-2:3.10.3-12.el10_2.10, freerdp-server-2:3.10.3-12.el10_2.10, libwinpr-devel-2:3.10.3-12.el10_2.10
- RHSA-2026:61379 Released 2026-08-31 · Red Hat rating Importantfreerdp security update
- Red Hat Enterprise Linux AppStream (v. 9) freerdp-2:2.11.7-7.el9_8.6, freerdp-libs-2:2.11.7-7.el9_8.6, libwinpr-2:2.11.7-7.el9_8.6
- Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) freerdp-devel-2:2.11.7-7.el9_8.6, libwinpr-devel-2:2.11.7-7.el9_8.6
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
FreeRDP 3.29.0
21 records Highest priority Priority HIGH 11 HIGH, 9 MEDIUM, 1 LOW
Other records, highest priority first
- TI-2026-47600 FreeRDP before 3.29.0 NULL Dereference via smartcard cleanupPriority HIGH 77
- TI-2026-47595 FreeRDP before 3.29.0 Use-After-Free via WindowIcon async messagePriority HIGH 77
- TI-2026-47594 FreeRDP 3.28.0 Heap Buffer Overflow via RAIL orderLength UnderflowPriority HIGH 77
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat CodeReady Linux Builder EUS (v.9.6) | Fixed | RHSA-2026:71387 |
| Red Hat Enterprise Linux AppStream (v. 10) | Fixed | RHSA-2026:61378 |
| Red Hat Enterprise Linux AppStream (v. 8) | Fixed | RHSA-2026:62571 |
| Red Hat Enterprise Linux AppStream (v. 9) | Fixed | RHSA-2026:61379 |
| Red Hat Enterprise Linux AppStream AUS (v.8.4) | Fixed | RHSA-2026:65855 |
| Red Hat Enterprise Linux AppStream AUS (v.8.6) | Fixed | RHSA-2026:66281 |
| Red Hat Enterprise Linux AppStream E4S (v.8.8) | Fixed | RHSA-2026:66282 |
| Red Hat Enterprise Linux AppStream E4S (v.9.2) | Fixed | RHSA-2026:71388 |
| Red Hat Enterprise Linux AppStream E4S (v.9.4) | Fixed | RHSA-2026:71390 |
| Red Hat Enterprise Linux AppStream EUS (v. 10.0) | Fixed | RHSA-2026:68706 |
| Red Hat Enterprise Linux AppStream EUS (v.9.6) | Fixed | RHSA-2026:71387 |
| Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) | Fixed | RHSA-2026:65855 |
| Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) | Fixed | RHSA-2026:66281 |
| Red Hat Enterprise Linux AppStream TUS (v.8.8) | Fixed | RHSA-2026:66282 |
| Red Hat Enterprise Linux CRB (v. 8) | Fixed | RHSA-2026:62571 |
| Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) | Fixed | RHSA-2026:61378 |
| Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) | Fixed | RHSA-2026:61379 |
| Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) | Fixed | RHSA-2026:68706 |
| Red Hat Enterprise Linux Server (v. 7 ELS) | Fixed | RHSA-2026:68707 |
| Red Hat Enterprise Linux Server Optional (v. 7 ELS) | Fixed | RHSA-2026:68707 |
Not affected: 1 product
- Red Hat Enterprise Linux 6
Timeline
- 2026-10-02 Threatist record created from CVE-2026-67301
- 2026-10-03 Alias added: GHSA-vpv4-cm44-pgmc
- 2026-10-14 EPSS moved to the 50th–90th percentile
References
Patch 1
More Freerdp vulnerabilities
- TI-2026-85092 Use-after-free in FreeRDP rdpgfx channel close handling CVSS 4.0CRITICAL 9.3
- TI-2026-85091 Out-of-bounds write in FreeRDP proxy via bitmap cache v2 capability CVSS 4.0CRITICAL 9.3
- TI-2026-24435 FreeRDP has a `size_t` underflow in ADPCM decoder leads to heap-buffer-overflow write CVSS 3.1CRITICAL 9.8
- TI-2023-21373 Out-Of-Bounds Write in FreeRDP CVSS 3.1CRITICAL 9.8
- TI-2022-08692 Server side NTLM does not properly check parameters in FreeRDP CVSS 3.1CRITICAL 9.1
- TI-2023-21374 Out-Of-Bounds Read in FreeRDP CVSS 3.1CRITICAL 9.1
Sources
- CVE-2026-67301 · CVE Program
- CVE-2026-67301 · NVD
- FIRST EPSS
- GHSA-vpv4-cm44-pgmc · GitHub Advisory Database · CC BY 4.0
- CVE-2026-67301 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences