Security readout for executives and security teams
Plain-English summary
CVE-2026-27015 can let a malicious Remote Desktop server crash a vulnerable FreeRDP client. The business impact is denial of service to users or workflows relying on FreeRDP. It requires user interaction and smartcard redirection, so exposure is narrower than a default remote compromise issue.
Executive priority
Treat as a targeted availability risk for FreeRDP-dependent users, not an enterprise-wide emergency. Prioritize patching where smartcard redirection is used or users connect to third-party RDP servers. Standard update cycles are reasonable unless FreeRDP availability is business-critical.
Technical view
FreeRDP before 3.23.0 has a missing bounds check in smartcard_unpack_read_size_align() in libfreerdp/utils/smartcard_pack.c. Malformed smartcard NDR alignment padding can reach WINPR_ASSERT and abort the client in affected upstream builds where WITH_VERBOSE_WINPR_ASSERT is enabled. The issue is classified as CWE-617 and has CVSS 4.0 score 5.0.
Likely exposure
Most relevant to organizations using FreeRDP clients below 3.23.0 with smartcard redirection enabled. Exposure increases when users connect to untrusted, external, or attacker-controlled RDP servers. Systems not using smartcard redirection are not described as affected by the trigger in the provided sources.
Exploitation context
The source bundle does not indicate known active exploitation, and the CVE is not listed as KEV. Exploitation requires a malicious RDP server, user interaction, and smartcard redirection. The documented outcome is client crash, not data theft, code execution, or server compromise.
Researcher notes
Key conditions are FreeRDP version below 3.23.0, smartcard redirection enabled, and builds where the reachable WINPR_ASSERT aborts. The public description points to a missing bounds check in smartcard NDR alignment handling. Avoid assuming broader impact beyond client denial of service without additional vendor evidence.
Mitigation direction
- Upgrade FreeRDP clients to version 3.23.0 or later.
- Disable smartcard redirection where it is not required.
- Restrict connections to trusted RDP servers until clients are updated.
- Review FreeRDP vendor guidance and downstream package advisories.
Validation and detection
- Inventory FreeRDP client versions across endpoints and images.
- Identify clients below FreeRDP 3.23.0.
- Check whether smartcard redirection or smartcard logon is enabled.
- Confirm whether builds use verbose WinPR asserts.
- Verify updated clients report FreeRDP 3.23.0 or later.
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-617: Exact CWE lookup
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Open ATT&CK lookupCVE-2026-27015 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 (4.0)
- Known Exploited
- No
- Published
Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/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:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P——Primary CVE scoreVulnerability scoring details
Base CVSS 4.0 score
5MediumVector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/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-7g72-39pq-4725CVE reference · x_refsource_CONFIRM
- https://github.com/FreeRDP/FreeRDP/commit/65d59d3b3c2f630f2ea862687ecf5f95f8115244CVE 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.
Reachable Assertion
Reachable Assertion represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.