CVE-2026-55639

MEDIUMPre-NVD 5.35.3—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 5.3 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3%, top 83% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
5.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.3Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

xrdp is an open source RDP server. Versions 0.10.6 and prior contain a vulnerability concerning the parsing of Client Security Data within the Client MCS Connect Initial PDU with GCC Conference Create Request during the connection sequence. During the initial capability and security negotiation phase, the parser fails to perform sufficient length validation for the incoming data block. A remote, unauthenticated attacker could potentially exploit this flaw by sending a specially crafted RDP packet containing malformed data. Due to missing bounds checks, the xrdp process may read a small number of bytes beyond the declared data block boundary, potentially disclosing process memory contents that could be combined with other vulnerabilities. This issue has been fixed in version 0.10.6.1.

CVSS v3
5.3
EG Score
5.3(medium)
EG Risk
39(Track)
EG Risk 39/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity53% × 45%
Exploitation0% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
17%
KEV
Not listed

Published

July 20, 2026

Last Modified

July 29, 2026

Advisory Details (2)

Auto-updated Jul 20, 2026
Patch available. Sources: github_release, github.
github Patch Available

Improper Input Validation in xrdp MCS Data Processing Leading to Potential Information Leak · Advisory · neutrinolabs/xrdp · GitHub

https://github.com/neutrinolabs/xrdp/security/advisories/GHSA-6g36-mxcf-r3gc
github_release Patch Available

xrdp v0.10.6.1

Patch available: neutrinolabs/xrdp v0.10.6.1

https://github.com/neutrinolabs/xrdp/releases/tag/v0.10.6.1

Affected Packages

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
xrdp0.10.0-1 ... 0.9.24-5~bpo12+1 (43 versions)——
Debian:12(1)
PackageVulnerable rangeFixed inDependents
xrdp0.10.0-1 ... 0.9.24-5~bpo12+1 (36 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
xrdp0.10.1-3.1 ... 0.10.6.1-2 (20 versions)——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
xrdp0.10.1-3.1 ... 0.10.6.1-1 (18 versions)0.10.6.1-2—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 10× in last 7d / 51× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-08-30 02:33 UTCEG score recompute
  2. 2026-08-30 01:22 UTCEPSS rescore
  3. 2026-08-28 21:41 UTCEPSS rescore
  4. 2026-08-27 15:13 UTCEG score recompute
  5. 2026-08-27 14:25 UTCEPSS rescore
  6. 2026-08-26 14:46 UTCEPSS rescore
  7. 2026-08-26 12:58 UTCEG score recompute
  8. 2026-08-25 13:49 UTCEPSS rescore
  9. 2026-08-25 11:14 UTCEG score recompute
  10. 2026-08-24 09:27 UTCEG score recompute
  11. 2026-08-23 07:42 UTCEG score recompute
  12. 2026-08-23 00:19 UTCEPSS rescore
  13. 2026-08-22 05:58 UTCEG score recompute
  14. 2026-08-21 23:49 UTCEPSS rescore
  15. 2026-08-21 04:14 UTCEG score recompute
  16. 2026-08-20 22:55 UTCEPSS rescore
  17. 2026-08-20 02:30 UTCEG score recompute
  18. 2026-08-19 17:04 UTCEPSS rescore
  19. 2026-08-19 00:45 UTCEG score recompute
  20. 2026-08-18 13:48 UTCEPSS rescore
  21. 2026-08-17 23:01 UTCEG score recompute
  22. 2026-08-17 13:47 UTCEPSS rescore
  23. 2026-08-16 21:16 UTCEG score recompute
  24. 2026-08-16 14:56 UTCEPSS rescore
  25. 2026-08-16 02:14 UTCEPSS rescore
Show 47 more
  1. 2026-08-15 19:32 UTCEG score recompute
  2. 2026-08-15 01:30 UTCEPSS rescore
  3. 2026-08-14 17:47 UTCEG score recompute
  4. 2026-08-13 22:00 UTCEPSS rescore
  5. 2026-08-12 14:06 UTCEG score recompute
  6. 2026-08-12 13:51 UTCEPSS rescore
  7. 2026-08-11 12:21 UTCEG score recompute
  8. 2026-08-11 00:00 UTCEPSS rescore
  9. 2026-08-10 10:37 UTCEG score recompute
  10. 2026-08-09 13:46 UTCEPSS rescore
  11. 2026-08-09 08:51 UTCEG score recompute
  12. 2026-08-08 16:37 UTCEPSS rescore
  13. 2026-08-08 07:07 UTCEG score recompute
  14. 2026-08-07 05:23 UTCEG score recompute
  15. 2026-08-06 13:47 UTCEPSS rescore
  16. 2026-08-06 03:39 UTCEG score recompute
  17. 2026-08-05 19:17 UTCEPSS rescore
  18. 2026-08-05 01:55 UTCEG score recompute
  19. 2026-08-04 15:10 UTCEPSS rescore
  20. 2026-08-04 10:39 UTCEPSS rescore
  21. 2026-08-04 00:10 UTCEG score recompute
  22. 2026-08-03 10:36 UTCEPSS rescore
  23. 2026-08-02 22:25 UTCEG score recompute
  24. 2026-08-02 02:27 UTCEPSS rescore
  25. 2026-08-01 20:40 UTCEG score recompute
  26. 2026-08-01 04:16 UTCEPSS rescore
  27. 2026-07-30 17:10 UTCEG score recompute
  28. 2026-07-30 16:28 UTCEPSS rescore
  29. 2026-07-30 01:30 UTCEPSS rescore
  30. 2026-07-29 15:25 UTCEG score recompute
  31. 2026-07-28 15:37 UTCEPSS rescore
  32. 2026-07-28 14:18 UTCEG score recompute
  33. 2026-07-27 12:31 UTCEG score recompute
  34. 2026-07-26 14:54 UTCEPSS rescore
  35. 2026-07-26 10:46 UTCEG score recompute
  36. 2026-07-25 14:18 UTCEPSS rescore
  37. 2026-07-24 14:18 UTCEPSS rescore
  38. 2026-07-23 14:18 UTCEPSS rescore
  39. 2026-07-23 03:20 UTCEG score recompute
  40. 2026-07-22 23:34 UTCEG score recompute
  41. 2026-07-22 14:08 UTCEPSS rescore
  42. 2026-07-21 15:25 UTCEPSS rescore
  43. 2026-07-20 20:44 UTCEG score recompute
  44. 2026-07-20 19:14 UTCEG score recompute
  45. 2026-07-20 18:41 UTCEG score recompute
  46. 2026-07-20 17:58 UTCEG score recompute
  47. 2026-07-20 17:57 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-55639?
CVE-2026-55639 is a medium vulnerability published on July 20, 2026. xrdp is an open source RDP server. Versions 0.10.6 and prior contain a vulnerability concerning the parsing of Client Security Data within the Client MCS Connect Initial PDU with GCC Conference Create Request during the connection sequence. During the initial capability and security negotiation…
When was CVE-2026-55639 disclosed?
CVE-2026-55639 was first published in the National Vulnerability Database on July 20, 2026, with the most recent update on July 29, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-55639 actively exploited?
CVE-2026-55639 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 83.3% of all scored CVEs.
What is the CVSS score of CVE-2026-55639?
CVE-2026-55639 has a CVSS v3 base score of 5.3 (NVD).
How do I remediate CVE-2026-55639?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-55639, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-55639

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