PatchTheCVECVE-2026-33977: FreeRDP is a free implementation of the Remote Desktop Protocol
CVE-2026-33977 is a medium-severity flaw (CVSS 6.5) affecting freerdp. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.24.2, a malicious RDP server can crash the FreeRDP client by sending audio data in IMA ADPCM format with an invalid initial step index value (>= 89). The unvalidated step index is read directly from the network and used to index into a 89-entry lookup table, triggering a WINPR_ASSERT() failure and process abort via SIGABRT. This affects any FreeRDP client that has
Why this priority
- Public exploit reference
A fixed release or distro patch exists.
Risk facts
| CVSS score | 6.5 (Medium) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | Required |
| EPSS exploit chance | 0.3% (top 82%) |
| CISA exploited list | No |
| Weakness | CWE-617 |
| Published | 2026-03-30 |
| Last modified | 2026-06-17 |
Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-33977?
freerdp: upgrade to 3.24.2. Exact commands for each OS are on this page.
Is CVE-2026-33977 being exploited?
CVE-2026-33977 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-33977 affect?
CVE-2026-33977 affects freerdp. Severity is medium (CVSS 6.5). FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.24.2, a malicious RDP server can crash the FreeRDP client by sending audio data in IMA ADPCM format with an invalid initial step index value (>= 89). The un
How urgent is CVE-2026-33977?
Priority 32/100. Public exploit reference
Software pages
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