Is there a public exploit for CVE-2026-121399?

No public exploit for CVE-2026-121399 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-121399?

CVE-2026-121399 scores CVSS 5.3 (v4.0), rated medium.

What does CVE-2026-121399 affect?

CVE-2026-121399 affects FreeRDP FreeRDP.

5.3 Medium

FreeRDP before 3.32.2 contains a memory allocation vulnerability in rdgreceivepacket that allows a malicious RD Gateway to force a 2 GiB…

CVE-2026-121399

FreeRDP before 3.32.2 contains a memory allocation vulnerability in rdgreceivepacket that allows a malicious RD Gateway to force a 2 GiB client allocation before tunnel authentication. Attackers can send an eight-byte RDG header declaring packet length 0x7FFFFFFF to trigger pre-authentication memory exhaustion and denial of service.

Assessment

CVSS: 5.3 (v4.0)
Severity: Medium
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 3 November 2026
Last updated: 3 November 2026
Affected: FreeRDP · FreeRDP
Assigner: VulnCheck

CVSS vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

At the source

EUVD (ENISA)

References

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