Double free in FreeRDP WinPR Kerberos allows remote server crash
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 4 without a fix
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-415 and the CVSS impact.
Summary
FreeRDP before 3.32.2 contains a double free (CWE-415) in the WinPR Kerberos SSPI retrieveSomeTgt function, which installs the krb5 default into a target principal with an empty domain, without taking ownership of it. An unauthenticated remote client can send a crafted NLA/CredSSP request to corrupt the heap and crash the server process. A public exploit is linked in the references.
Written with Claude Haiku 5.5 from the sources below · 2026-11-06
Description from the CNA
FreeRDP before 3.32.2 contains a double free in the WinPR Kerberos SSPI retrieveSomeTgt function, which installs the krb5 default realm into a target principal that has an empty realm without taking ownership of it. Unauthenticated remote clients can send a crafted NLA/CredSSP u2u TGT request whose server-name component contains '@' to corrupt the heap and crash the server process.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
Upgrade FreeRDP to 3.32.2, which fixes the flaw. Red Hat Enterprise Linux 7, 8, 9 and 10 are listed as affected without a fix, and Red Hat lists no plan for them.
Written with Claude Haiku 5.5 from the sources below · 2026-11-06
- Fix · CNA FreeRDP (FreeRDP) Fixed in 3.32.2
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
FreeRDP 3.32.2
14 records Highest priority Priority HIGH 11 HIGH, 3 MEDIUM
Other records, highest priority first
- TI-2026-85092 Use-after-free in FreeRDP rdpgfx channel close handlingPriority HIGH 81
- TI-2026-85091 Out-of-bounds write in FreeRDP proxy via bitmap cache v2 capabilityPriority HIGH 81
- TI-2026-85103 Heap buffer overflow in FreeRDP RD Gateway RPC clientPriority HIGH 77
Vendor assessments
Red Hat
Red Hat rating: Important. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix yet |
| Red Hat Enterprise Linux 7 | Affected | No fix yet |
| Red Hat Enterprise Linux 8 | Affected | No fix yet |
| Red Hat Enterprise Linux 9 | Affected | No fix yet |
Not affected: 1 product
- Red Hat Enterprise Linux 6
Timeline
- 2026-11-04 Threatist record created from CVE-2026-121956
- 2026-11-04 Alias added: GHSA-fg26-fr9r-9hrq
- 2026-11-04 CISA SSVC decision points changed
- 2026-11-04 Priority changed: MEDIUM → HIGH
- 2026-11-06 Affected versions changed · Red Hat
- 2026-11-06 CVSS score added · Red Hat
- 2026-11-06 Affected versions changed · Red Hat
References
More Freerdp vulnerabilities
- 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
Sources
- CVE-2026-121956 · CVE Program
- CVE-2026-121956 · NVD
- FIRST EPSS
- GHSA-fg26-fr9r-9hrq · GitHub Advisory Database · CC BY 4.0
- CVE-2026-121956 · Red Hat security data · CC BY 4.0
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