CVE-2026-55238
CVE-2026-55238 — xrdp: Malformed Confirm Active capability sets cause out-of-bounds reads
xrdp is an open source RDP server. Versions 0.10.6 and prior contain a vulnerability concerning the processing of RDP Confirm Active PDU, where during the capability negotiation phase, the parser did not perform sufficient length validation for specific capability sets. A remote, unauthenticated attacker could potentially exploit this flaw by sending a specially crafted RDP packet containing malformed capability data. Due to missing bounds checks, the xrdp process may perform out-of-bounds memory reads, which can result in the termination of the service (Denial of Service). However, since xrdp forks a new process for each connection by default, an out-of-bounds read causing a process crash is unlikely to bring down the entire xrdp service. This issue has been fixed in version 0.10.6.1.
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
5.3
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
Yes
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 |
|---|---|---|---|---|---|
| 5.3 | CVSS 3.1 | MEDIUM | — | — | cvelistV5 |
Weakness & attack patterns
- CWE-126
References
2 on the record
- github.com/neutrinolabs/xrdp/security/advisories/GHSA-mg8j-x9rw-9xv3
x_refsource_CONFIRM
- github.com/neutrinolabs/xrdp/releases/tag/v0.10.6.1
x_refsource_MISC
Elsewhere on this site
- neutrinolabsevery CVE for this vendor
- CWE-126other pages naming this weakness
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.