Security readout for executives and security teams
Plain-English summary
CVE-2026-22852 affects FreeRDP clients before 3.20.1. A malicious RDP server can crash or corrupt memory in a connecting client while audio input formats are processed. This matters most where users connect to untrusted or externally controlled RDP servers. The vendor states the issue is fixed in FreeRDP 3.20.1.
Executive priority
Treat as a timely client-side patching issue, not an emergency internet-facing server event. Prioritize developer workstations, jump hosts, support systems, and any environment where staff use FreeRDP to connect to third-party or less-trusted RDP services.
Technical view
The flaw is a heap-buffer-overflow write in audin_process_formats, classified as CWE-787. FreeRDP reuses callback->formats_count across multiple MSG_SNDIN_FORMATS PDUs and can write past a newly allocated formats array. The CVSS v4.0 score is 6.8 with network attack vector, high attack complexity, no privileges required, and user interaction required.
Likely exposure
Organizations using FreeRDP client versions before 3.20.1 are potentially exposed, especially where users initiate RDP sessions to servers outside trusted administration paths. Exposure depends on whether FreeRDP clients are deployed and whether audio input redirection/AUDIN processing is reachable in normal use.
Exploitation context
The source bundle does not identify active exploitation, and this CVE is not marked KEV. Exploitation requires a user to connect a vulnerable FreeRDP client to a malicious RDP server. Reported impact is memory corruption and crash, with CVSS indicating high confidentiality, integrity, and availability impact within the vulnerable client context.
Researcher notes
Evidence is strongest for vulnerable versions, root cause, and fixed version. The public bundle does not provide active exploitation evidence, exploit details, or alternative mitigations beyond upgrading. Validate downstream package versions because Linux distributions may backport the fix without using upstream version 3.20.1.
Mitigation direction
- Upgrade FreeRDP to version 3.20.1 or later.
- Prioritize systems where users connect to untrusted RDP servers.
- Restrict RDP connections to trusted destinations where operationally feasible.
- Review FreeRDP vendor advisory and release notes for deployment-specific guidance.
Validation and detection
- Inventory endpoints and applications using FreeRDP.
- Confirm installed FreeRDP versions are 3.20.1 or later.
- Identify users or workflows connecting to external RDP servers.
- Check software distribution channels for patched FreeRDP packages.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-787: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2026-22852 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 6.8 (4.0)
- Known Exploited
- No
- Published
Vector: CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P——Primary CVE scoreVulnerability scoring details
Base CVSS 4.0 score
6.8MediumVector: CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-9chc-g79v-4qq4CVE reference · x_refsource_CONFIRM
- https://github.com/FreeRDP/FreeRDP/releases/tag/3.20.1CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Out-of-bounds Write
Out-of-bounds Write represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.