Security readout for executives and security teams
Plain-English summary
CVE-2022-39320 affects FreeRDP clients before 2.9.0 when USB redirection is used. A malicious RDP server can cause the client to mishandle memory and send unintended client-side data back. This is not listed in KEV, and the provided sources do not show active exploitation.
Executive priority
Treat this as a targeted client-side exposure, not an internet-wide emergency. Patch in normal vulnerability cycles, but accelerate for teams using FreeRDP with USB redirection against external or contractor-managed RDP servers.
Technical view
The flaw is in FreeRDP's urbdrc channel. Narrow integer addition can under-allocate a buffer before data is written, causing out-of-bounds memory access. The published CVSS 3.1 score is 5.5 with network attack vector, required user interaction, low privileges, and low confidentiality, integrity, and availability impact.
Likely exposure
Exposure is most likely on endpoints, jump hosts, or tooling using FreeRDP versions before 2.9.0 with the /usb redirection switch enabled. Risk rises when users connect FreeRDP clients to third-party, internet-hosted, or otherwise untrusted RDP servers.
Exploitation context
The attacker position described is a malicious RDP server interacting with a vulnerable FreeRDP client. The bundle marks KEV as false and provides no cited evidence of exploitation in the wild, public exploit use, or broader affected product families beyond FreeRDP.
Researcher notes
The primary evidence identifies FreeRDP before 2.9.0 and the urbdrc USB redirection path. The issue is described as out-of-bounds read behavior caused by too-narrow integer addition and insufficient allocation. No source in the bundle supports claims of active exploitation.
Mitigation direction
- Upgrade FreeRDP to 2.9.0 or a distributor package containing the fix.
- Disable USB redirection; do not use the /usb switch until upgraded.
- Prioritize systems connecting to untrusted or external RDP servers.
- Track applicable Fedora, Gentoo, and Debian package advisories for packaged deployments.
Validation and detection
- Inventory installed FreeRDP client versions across endpoints and administration hosts.
- Check whether FreeRDP usage includes USB redirection or the /usb switch.
- Confirm vulnerable clients are upgraded to 2.9.0 or a fixed vendor package.
- Review RDP connection policies for exposure to untrusted servers.
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-125: Exact CWE lookup
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Open ATT&CK lookupCVE-2022-39320 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
- 5.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:L
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:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:L2.13.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
5.5MediumVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:L
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-qfq2-82qr-7f4jCVE reference
- FEDORA-2022-fd6e43dec8CVE reference · vendor-advisory
- FEDORA-2022-076b1c9978CVE reference · vendor-advisory
- GLSA-202401-16CVE reference · vendor-advisory
- https://lists.debian.org/debian-lts-announce/2025/02/msg00034.htmlCVE reference
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 Read
Out-of-bounds Read represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.