TI-2020-10965 Aliases CVE-2020-13998 GHSA-5x67-frfj-mmvh

Citrix XenApp 6.5, when 2FA is enabled, allows a remote unauthenticated attacker to…

MEDIUM 42CWE-639Published 2020-06-11 · Updated 2024-08-04

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: Security bypass, Information disclosure
Confidentiality · integrity · availability: High · None · None
Fix status: No fix listed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-639 and CWE-203.

Summary

Citrix XenApp 6.5, when 2FA is enabled, allows a remote unauthenticated attacker to ascertain whether a user exists on the server, because the 2FA error page only occurs after a valid username is entered. NOTE: This vulnerability only affects products that are no longer supported by the maintainer

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.01424 73rd percentileScored 2026-11-07

Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: Yes
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
—	—	all versions	—	No fix listed	CNA

— Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:citrix:xenapp:6.5.0.0:::::::*	6.5.0.0	Vulnerable	Citrix

cpe:2.3:a:citrix:xenapp:6.5.0.0:*:*:*:*:*:*:* Versions 6.5.0.0 Vulnerable ·Citrix

Remediation

No fixed version listed by the sources yet.

Timeline

2026-10-02 Threatist record created from CVE-2020-13998
2026-10-03 Alias added: GHSA-5x67-frfj-mmvh

References

Advisory 1

https://gist.github.com/kampji/11e259d68ad98a6f0f898132f1961a96

TI-2012-04351 The XML Service interface in Citrix XenApp 6.5 and 6.5 Feature Pack 1 allows remote… CVSS 2.0HIGH 9.3
TI-2016-05565 Citrix XenApp 6.x before 6.5 HRP07 and 7.x before 7.9 and Citrix XenDesktop before 7.9… CVSS 3.0CRITICAL 9.8
TI-2020-06700 Improper privilege management in Citrix Virtual Apps and Desktops CVSS 3.1HIGH 8.8
TI-2020-06686 Improper privilege management in Citrix Virtual Apps and Desktops CVSS 3.1HIGH 8.8
TI-2009-02341 Citrix XenApp (formerly Presentation Server) 4.5 Hotfix Rollup Pack 3 does not apply an… CVSS 2.0HIGH 7.5
TI-2021-05789 A vulnerability has been identified in Citrix Virtual Apps and Desktops that could, if… CVSS 3.1HIGH 7.8

See all 8 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences