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TI-2026-24361 Aliases CVE-2026-31806

FreeRDP has a Heap Buffer Overflow in nsc_process_message() via Unchecked SURFACE_BITS_COMMAND Bitmap Dimensions

Priority MEDIUM 49CWE-122Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-122 and the CVSS impact.

Summary

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.24.0, the gdi_surface_bits() function processes SURFACE_BITS_COMMAND messages sent by the RDP server. When the command is handled using NSCodec, the bmp.width and bmp.height values provided by the server are not properly validated against the actual desktop dimensions. A malicious RDP server can supply crafted bmp.width and bmp.height values that exceed the expected surface size. Because these values are used during bitmap decoding and memory operations without proper bounds checking, this can lead to a heap buffer overflow. Since the attacker can also control the associated pixel data transmitted by the server, the overflow may be exploitable to overwrite adjacent heap memory. This vulnerability is fixed in 3.24.0.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00682 52nd percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed FreeRDP (FreeRDP): 3.24.0Red Hat: 14 advisories

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Total

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 3.24.03.24.0Patch availableCNA
  • FreeRDP VendorFreeRDP Affected before 3.24.0 Fixed in 3.24.0 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:*before 3.24.0VulnerableFreeRDP
  • cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:* Versions before 3.24.0 Vulnerable ·FreeRDP

Remediation

  • Fix · CNA FreeRDP (FreeRDP) Fixed in 3.24.0

Red Hat 14 advisories

  • RHSA-2026:19033 Released 2026-05-19 · Red Hat rating Important
    freerdp security update
    • Red Hat Enterprise Linux AppStream (v. 10) freerdp-2:3.10.3-12.el10_2.2, freerdp-libs-2:3.10.3-12.el10_2.2, libwinpr-2:3.10.3-12.el10_2.2
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) freerdp-devel-2:3.10.3-12.el10_2.2, freerdp-server-2:3.10.3-12.el10_2.2, libwinpr-devel-2:3.10.3-12.el10_2.2
  • RHSA-2026:11323 Released 2026-04-28 · Red Hat rating Important
    freerdp security update
    • Red Hat Enterprise Linux Server (v. 7 ELS) freerdp-2.1.1-5.el7_9.7, freerdp-libs-2.1.1-5.el7_9.7, freerdp-libs-2.1.1-5.el7_9.7.ppc +2
    • Red Hat Enterprise Linux Server Optional (v. 7 ELS) freerdp-devel-2.1.1-5.el7_9.7, freerdp-devel-2.1.1-5.el7_9.7.ppc, libwinpr-devel-2.1.1-5.el7_9.7 +1
  • RHSA-2026:10951 Released 2026-04-27 · Red Hat rating Important
    freerdp security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.6) freerdp-2:2.2.0-7.el8_6.5, freerdp-libs-2:2.2.0-7.el8_6.5, libwinpr-2:2.2.0-7.el8_6.5 +1
    • Red Hat Enterprise Linux AppStream E4S (v.8.6) freerdp-2:2.2.0-7.el8_6.5, freerdp-libs-2:2.2.0-7.el8_6.5, libwinpr-2:2.2.0-7.el8_6.5 +1
    • Red Hat Enterprise Linux AppStream TUS (v.8.6) freerdp-2:2.2.0-7.el8_6.5, freerdp-libs-2:2.2.0-7.el8_6.5, libwinpr-2:2.2.0-7.el8_6.5 +1
Show 11 more Red Hat advisories
  • RHSA-2026:10735 Released 2026-04-27 · Red Hat rating Important
    freerdp security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.4) freerdp-2:2.2.0-12.el8_4, freerdp-libs-2:2.2.0-12.el8_4, libwinpr-2:2.2.0-12.el8_4 +1
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) freerdp-2:2.2.0-12.el8_4, freerdp-libs-2:2.2.0-12.el8_4, libwinpr-2:2.2.0-12.el8_4 +1
  • RHSA-2026:10734 Released 2026-04-27 · Red Hat rating Important
    freerdp security update
    • Red Hat Enterprise Linux AppStream AUS (v. 8.2) freerdp-2:2.0.0-46.rc4.el8_2.10, freerdp-libs-2:2.0.0-46.rc4.el8_2.10, libwinpr-2:2.0.0-46.rc4.el8_2.10 +1
  • RHSA-2026:10076 Released 2026-04-23 · Red Hat rating Important
    freerdp security update
    • Red Hat Enterprise Linux AppStream E4S (v.8.8) freerdp-2:2.2.0-12.el8_8.5, freerdp-libs-2:2.2.0-12.el8_8.5, libwinpr-2:2.2.0-12.el8_8.5 +1
    • Red Hat Enterprise Linux AppStream TUS (v.8.8) freerdp-2:2.2.0-12.el8_8.5, freerdp-libs-2:2.2.0-12.el8_8.5, libwinpr-2:2.2.0-12.el8_8.5 +1
  • RHSA-2026:9641 Released 2026-04-22 · Red Hat rating Important
    freerdp security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.2) freerdp-2:2.4.1-6.el9_2.6, freerdp-libs-2:2.4.1-6.el9_2.6, libwinpr-2:2.4.1-6.el9_2.6
  • RHSA-2026:9640 Released 2026-04-22 · Red Hat rating Important
    freerdp security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.0) freerdp-2:2.4.1-3.el9_0.4, freerdp-libs-2:2.4.1-3.el9_0.4, libwinpr-2:2.4.1-3.el9_0.4
  • RHSA-2026:6958 Released 2026-04-08 · Red Hat rating Important
    freerdp security update
    • Red Hat CodeReady Linux Builder EUS (v.9.4) freerdp-devel-2:2.11.2-1.el9_4.5, libwinpr-devel-2:2.11.2-1.el9_4.5
    • Red Hat Enterprise Linux AppStream EUS (v.9.4) freerdp-2:2.11.2-1.el9_4.5, freerdp-libs-2:2.11.2-1.el9_4.5, libwinpr-2:2.11.2-1.el9_4.5
  • RHSA-2026:6918 Released 2026-04-07 · Red Hat rating Important
    freerdp security update
    • Red Hat Enterprise Linux AppStream (v. 8) freerdp-2:2.11.7-6.el8_10, freerdp-libs-2:2.11.7-6.el8_10, libwinpr-2:2.11.7-6.el8_10 +1
    • Red Hat Enterprise Linux CRB (v. 8) freerdp-devel-2:2.11.7-6.el8_10
  • RHSA-2026:6799 Released 2026-04-07 · Red Hat rating Important
    freerdp security update
    • Red Hat Enterprise Linux AppStream (v. 10) freerdp-2:3.10.3-5.el10_1.5, freerdp-libs-2:3.10.3-5.el10_1.5, libwinpr-2:3.10.3-5.el10_1.5
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) freerdp-devel-2:3.10.3-5.el10_1.5, freerdp-server-2:3.10.3-5.el10_1.5, libwinpr-devel-2:3.10.3-5.el10_1.5
  • RHSA-2026:6743 Released 2026-04-07 · Red Hat rating Important
    freerdp security update
    • Red Hat Enterprise Linux AppStream EUS (v. 10.0) freerdp-2:3.10.3-3.el10_0.5, freerdp-libs-2:3.10.3-3.el10_0.5, libwinpr-2:3.10.3-3.el10_0.5
    • Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) freerdp-devel-2:3.10.3-3.el10_0.5, freerdp-server-2:3.10.3-3.el10_0.5, libwinpr-devel-2:3.10.3-3.el10_0.5
  • RHSA-2026:6727 Released 2026-04-07 · Red Hat rating Important
    freerdp security update
    • Red Hat CodeReady Linux Builder EUS (v.9.6) freerdp-devel-2:2.11.7-1.el9_6.7, libwinpr-devel-2:2.11.7-1.el9_6.7
    • Red Hat Enterprise Linux AppStream EUS (v.9.6) freerdp-2:2.11.7-1.el9_6.7, freerdp-libs-2:2.11.7-1.el9_6.7, libwinpr-2:2.11.7-1.el9_6.7
  • RHSA-2026:6340 Released 2026-04-01 · Red Hat rating Important
    freerdp security update
    • Red Hat Enterprise Linux AppStream (v. 9) freerdp-2:2.11.7-1.el9_7.5, freerdp-libs-2:2.11.7-1.el9_7.5, libwinpr-2:2.11.7-1.el9_7.5
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) freerdp-devel-2:2.11.7-1.el9_7.5, libwinpr-devel-2:2.11.7-1.el9_7.5

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat CodeReady Linux Builder EUS (v.9.4)Fixed RHSA-2026:6958
Red Hat CodeReady Linux Builder EUS (v.9.6)Fixed RHSA-2026:6727
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:19033, RHSA-2026:6799
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2026:6918
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:6340
Red Hat Enterprise Linux AppStream AUS (v. 8.2)Fixed RHSA-2026:10734
Red Hat Enterprise Linux AppStream AUS (v.8.4)Fixed RHSA-2026:10735
Red Hat Enterprise Linux AppStream AUS (v.8.6)Fixed RHSA-2026:10951
Red Hat Enterprise Linux AppStream E4S (v.8.6)Fixed RHSA-2026:10951
Red Hat Enterprise Linux AppStream E4S (v.8.8)Fixed RHSA-2026:10076
Red Hat Enterprise Linux AppStream E4S (v.9.0)Fixed RHSA-2026:9640
Red Hat Enterprise Linux AppStream E4S (v.9.2)Fixed RHSA-2026:9641
Red Hat Enterprise Linux AppStream EUS (v. 10.0)Fixed RHSA-2026:6743
Red Hat Enterprise Linux AppStream EUS (v.9.4)Fixed RHSA-2026:6958
Red Hat Enterprise Linux AppStream EUS (v.9.6)Fixed RHSA-2026:6727
Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4)Fixed RHSA-2026:10735
Red Hat Enterprise Linux AppStream TUS (v.8.6)Fixed RHSA-2026:10951
Red Hat Enterprise Linux AppStream TUS (v.8.8)Fixed RHSA-2026:10076
Red Hat Enterprise Linux CRB (v. 8)Fixed RHSA-2026:6918
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2026:19033, RHSA-2026:6799
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2026:6340
Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0)Fixed RHSA-2026:6743
Red Hat Enterprise Linux Server (v. 7 ELS)Fixed RHSA-2026:11323
Red Hat Enterprise Linux Server Optional (v. 7 ELS)Fixed RHSA-2026:11323
Not affected: 1 product
  • Red Hat Enterprise Linux 6

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-31806
  2. 2026-10-11 EPSS moved to the 50th–90th percentile

References

Exploit 1

Patch 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