Freerdp3: Prior to 3.20.1, RDPEAR’s NDR array reader does not perform bounds checking on the on‑wire element count and can write past the heap buffer… (CVE-2026-22853)
FreeRDP versions prior to 3.20.1 contain a heap buffer overflow vulnerability in the RDPEAR NDR array reader due to lack of bounds checking on the on-wire element count. This flaw allows writing past the allocated heap buffer in the ndr_read_uint8Array function. The vulnerability has a high CVSS score of 9.8 and affects multiple Red Hat Enterprise Linux and Ubuntu package versions. It is fixed in FreeRDP version 3.20.1 and later. No known exploits in the wild have been reported. System updates from Red Hat and Ubuntu provide patches to remediate this issue.
AI Analysis
Technical Summary
CVE-2026-22853 is a heap buffer overflow vulnerability in FreeRDP's RDPEAR NDR array reader component. Prior to version 3.20.1, the function ndr_read_uint8Array does not perform bounds checking on the on-wire element count, which can lead to writing beyond the allocated heap buffer. This vulnerability is addressed in FreeRDP 3.20.1. Red Hat Enterprise Linux 10 and Ubuntu 25.10 and 24.04 LTS releases have issued security advisories and patches to fix this issue. The vulnerability has a CVSS 3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), indicating it is remotely exploitable without privileges or user interaction and can cause high impact on confidentiality, integrity, and availability.
Potential Impact
The vulnerability allows a remote attacker to cause a heap buffer overflow in FreeRDP clients by sending specially crafted RDP packets. This can lead to denial of service (crashes) or potentially arbitrary code execution with the privileges of the affected application. The CVSS score of 9.8 reflects the critical nature of the impact on confidentiality, integrity, and availability. No known active exploits have been reported at this time.
Mitigation Recommendations
A patch is available and the vulnerability is fixed in FreeRDP version 3.20.1. Users should update to this version or later. Red Hat and Ubuntu have released updated packages that address this issue; applying these vendor-provided updates will remediate the vulnerability. No additional mitigation steps are required beyond applying the official fixes.
Freerdp3: Prior to 3.20.1, RDPEAR’s NDR array reader does not perform bounds checking on the on‑wire element count and can write past the heap buffer… (CVE-2026-22853)
Description
FreeRDP versions prior to 3.20.1 contain a heap buffer overflow vulnerability in the RDPEAR NDR array reader due to lack of bounds checking on the on-wire element count. This flaw allows writing past the allocated heap buffer in the ndr_read_uint8Array function. The vulnerability has a high CVSS score of 9.8 and affects multiple Red Hat Enterprise Linux and Ubuntu package versions. It is fixed in FreeRDP version 3.20.1 and later. No known exploits in the wild have been reported. System updates from Red Hat and Ubuntu provide patches to remediate this issue.
CVSS v3.1
Score 9.8critical
Affected software
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-22853 is a heap buffer overflow vulnerability in FreeRDP's RDPEAR NDR array reader component. Prior to version 3.20.1, the function ndr_read_uint8Array does not perform bounds checking on the on-wire element count, which can lead to writing beyond the allocated heap buffer. This vulnerability is addressed in FreeRDP 3.20.1. Red Hat Enterprise Linux 10 and Ubuntu 25.10 and 24.04 LTS releases have issued security advisories and patches to fix this issue. The vulnerability has a CVSS 3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), indicating it is remotely exploitable without privileges or user interaction and can cause high impact on confidentiality, integrity, and availability.
Potential Impact
The vulnerability allows a remote attacker to cause a heap buffer overflow in FreeRDP clients by sending specially crafted RDP packets. This can lead to denial of service (crashes) or potentially arbitrary code execution with the privileges of the affected application. The CVSS score of 9.8 reflects the critical nature of the impact on confidentiality, integrity, and availability. No known active exploits have been reported at this time.
Mitigation Recommendations
A patch is available and the vulnerability is fixed in FreeRDP version 3.20.1. Users should update to this version or later. Red Hat and Ubuntu have released updated packages that address this issue; applying these vendor-provided updates will remediate the vulnerability. No additional mitigation steps are required beyond applying the official fixes.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:3068
- Cve Count
- 5
- Additional Cves
- ["CVE-2026-22855","CVE-2026-22858","CVE-2026-22859","CVE-2026-24678"]
Threat ID: 6a27e9938dd33fbd8516a7fe
Added to database: 06/09/2026, 10:23:15 UTC
Last enriched: 09/10/2026, 14:41:37 UTC
Last updated: 09/14/2026, 10:01:29 UTC
Views: 64
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