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TI-2026-47594 Aliases CVE-2026-67298GHSA-wrfm-6x9r-42cr

FreeRDP 3.28.0 Heap Buffer Overflow via RAIL orderLength Underflow

Priority HIGH 77CWE-191Published · Updated

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
Partial Red Hat: 6 fixed, 1 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-191 and the CVSS impact.

Summary

FreeRDP versions 3.28.0 and earlier contain a heap buffer overflow in the server-side RAIL channel handler (rail_server_handle_messages() in channels/rail/server/rail_main.c). When processing a RAIL PDU header, the code subtracts RAIL_PDU_HEADER_LENGTH from the peer-controlled orderLength field without first verifying orderLength is at least the header length. For orderLength values 0..3 this causes an unsigned integer underflow to a very large size, which bypasses the Stream_EnsureRemainingCapacity() capacity check (due to pointer arithmetic wraparound) and is then passed to WTSVirtualChannelRead(), resulting in an out-of-bounds heap write. A malicious or compromised RDP client can exploit this to corrupt the heap and crash the server. Fixed in FreeRDP 3.29.0.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00718 54th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial FreeRDP (FreeRDP): 3.29.0Red Hat: 3 advisoriesRed Hat: 6 fixed, 1 without a fix

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

VendorProductAffected versionsFixed inStatusSource
FreeRDPFreeRDPbefore 3.29.03.29.0Patch availableCNA
  • FreeRDP VendorFreeRDP Affected before 3.29.0 Fixed in 3.29.0 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:*before 3.29.0VulnerableFreeRDP
  • cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:* Versions before 3.29.0 Vulnerable ·FreeRDP

Remediation

  • Fix · CNA FreeRDP (FreeRDP) Fixed in 3.29.0

Red Hat 3 advisories

  • RHSA-2026:68707 Released 2026-09-17 · Red Hat rating Important
    freerdp 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 Important
    freerdp 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-2026:61378 Released 2026-08-31 · Red Hat rating Important
    freerdp 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

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-2026-47597 FreeRDP before 3.29.0 Out-of-bounds Read via Polygon async message-proxyPriority HIGH 77
    • TI-2026-47595 FreeRDP before 3.29.0 Use-After-Free via WindowIcon async messagePriority HIGH 77
    Show all 21 records →

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:61378
Red Hat Enterprise Linux AppStream EUS (v. 10.0)Fixed RHSA-2026:68706
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2026:61378
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: 2 products
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-67298
  2. 2026-10-03 Alias added: GHSA-wrfm-6x9r-42cr

References

Exploit 1

Patch 2

Advisory 1

  • 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
See all 336 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences