CVE-2026-63117
CVE-2026-63117 — FreeRDP: Denial of service through ADPCM frame size calculation
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.28.0, an authenticated RDP client can advertise DVI ADPCM with nBlockAlign equal to 8 and nChannels equal to 2 to make the `bs` calculation in rdpsnd_server_select_format in channels/rdpsnd/server/rdpsnd_main.c equal zero. The subsequent out_frames modulo `bs` operation raises SIGFPE and terminates the server-side rdpsnd channel process. This vulnerability fixed in 3.28.0.
Published Updated Sources: cvelistV5, GitHub_M
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.
Exploitation
Unreported
no source claims exploitation
EPSS
0%
chance of exploitation in 30 days
CVSS base
6.5
MEDIUM
CISA SSVC assessment
Three decision points CISA publishes for the CVEs it assesses · SSVC 2.0.3. A stakeholder decision, not a severity score.
Exploitation
None
none · proof-of-concept · active
Automatable
No
can an attacker script all four kill-chain steps
Technical impact
Partial
partial · total control of the vulnerable component
Affected scope
The catalog records vendors and products as separate lists, not pairs, so which product belongs to which vendor is not something this page can say.
Vendors (1)
Products (1)
Every base score collected
Sources score independently and disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Source |
|---|---|---|---|---|---|
| 6.5 | CVSS 3.1 | MEDIUM | — | — | cvelistV5 |
Weakness & attack patterns
- CWE-369
Detection
Read off the CVSS vector and the weakness class. Starting points, not rules we have tested.
- Search application, proxy, and WAF logs for requests touching /rdpsnd/server/rdpsnd_main.c.
References
4 on the record
- github.com/FreeRDP/FreeRDP/security/advisories/GHSA-v64m-xxfw-hrv6
x_refsource_CONFIRM
- github.com/FreeRDP/FreeRDP/pull/12980
x_refsource_MISC
- github.com/FreeRDP/FreeRDP/commit/b78fc0b138fe8f08a8b102e193ffb32986f4449a
x_refsource_MISC
- github.com/FreeRDP/FreeRDP/releases/tag/3.28.0
x_refsource_MISC
Elsewhere on this site
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.