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TI-2026-47161 Aliases CVE-2026-66402GHSA-759r-h698-g7xj

FreeRDP before 3.29.0 TLS Certificate Identity Validation Bypass

Priority MEDIUM 48CWE-295Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Spoofing
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 5 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-295.

Summary

FreeRDP before 3.29.0 (affected versions <= 3.28.0) contains multiple TLS certificate identity validation weaknesses in tls_verify_certificate(), tls_match_hostname(), and x509_utils_get_dns_names(). Because FreeRDP performs custom Common Name and DNS SAN string matching instead of using OpenSSL's length-aware identity validation APIs, it (1) truncates DNS SAN values at embedded NUL bytes (accepting e.g. 'victim.example\0.attacker.example' as 'victim.example'), (2) accepts a matching Common Name even when non-matching DNS SAN entries are present, and (3) accepts IP-literal targets via DNS/CN matching without comparing iPAddress SANs. Under a trusted or misissued certificate chain, an attacker positioned to present such a certificate can bypass server identity verification, weakening TLS server authentication.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0034 27th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial FreeRDP (FreeRDP): 3.29.0Red Hat: 5 without a fix

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 3.29.03.29.0Patch availableCNA
  • FreeRDP VendorFreeRDP Affected before 3.29.0 Fixed in 3.29.0 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:*before 3.29.0VulnerableFreeRDP
  • cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:* Versions before 3.29.0 Vulnerable ·FreeRDP

Remediation

  • Fix · CNA FreeRDP (FreeRDP) Fixed in 3.29.0

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    FreeRDP 3.29.0

    21 records Highest priority Priority HIGH 11 HIGH, 9 MEDIUM, 1 LOW

    Other records, highest priority first

    • TI-2026-47600 FreeRDP before 3.29.0 NULL Dereference via smartcard cleanupPriority HIGH 77
    • TI-2026-47597 FreeRDP before 3.29.0 Out-of-bounds Read via Polygon async message-proxyPriority HIGH 77
    • TI-2026-47595 FreeRDP before 3.29.0 Use-After-Free via WindowIcon async messagePriority HIGH 77
    Show all 21 records →

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 7AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 8AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-66402
  2. 2026-10-03 Alias added: GHSA-759r-h698-g7xj

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