Raw vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:NSummary
CVE-2020-8196 is a medium-severity Improper Access Control (CWE-284) vulnerability in Citrix Application Delivery Controller Firmware. Its CVSS base score is 4.3 (Medium).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 2% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog; a public proof-of-concept is referenced.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2020-8196 is an improper access control vulnerability, also referenced under CWE-284 and CWE-287, that affects Citrix ADC and Citrix Gateway versions prior to 13.0-58.30, 12.1-57.18, 12.0-63.21, 11.1-64.14, and 10.5-70.18, as well as Citrix SD-WAN WAN-OP versions prior to 11.1.1a, 11.0.3d, and 10.2.7. The flaw permits limited information disclosure and carries a CVSS 3.1 base score of 4.3 reflecting network attack vector, low complexity, and low privileges required.
Low-privileged authenticated users can exploit the issue over the network to obtain restricted information that should otherwise be inaccessible, as demonstrated by public proof-of-concept material describing local file inclusion behavior in the affected appliances.
Citrix advisory CTX276688 addresses the affected products and provides updated builds that resolve the access control weakness; organizations are advised to apply the listed version upgrades. The vulnerability is also catalogued by CISA among actively exploited issues, indicating confirmed real-world targeting of unpatched Citrix deployments.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2020-29073
Vulnerability Data
Improper access control in Citrix ADC and Citrix Gateway versions before 13.0-58.30, 12.1-57.18, 12.0-63.21, 11.1-64.14 and 10.5-70.18 and Citrix SDWAN WAN-OP versions before 11.1.1a, 11.0.3d and 10.2.7 resulting in limited information disclosure to low privileged users.
- CWE(s)
- KEV Date Added
- 03 November 2021
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 16 hardening rules · 6 OS baselines
V10.3.5V6.4.4V6.5.4V6.5.5
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
The awareness and training policy mandates training on access control practices, directly reducing the likelihood of improper access control weaknesses being introduced or exploited.
Training covers access control policies and the consequences of improper access grants or usage by users.
Security training teaches access control policies and enforcement, reducing improper access control implementations.
Provides capability to review session content, directly detecting violations of access control.
System audit review detects violations of access controls by identifying unauthorized access attempts.
Control assessments verify that access controls are implemented correctly and operating as intended, detecting improper access control before exploitation.
Requiring formal approval, documented controls, and responsibilities for inter-system exchanges directly enforces proper access control between systems.
Penetration testing simulates unauthorized access attempts, directly detecting and enabling remediation of improper access control weaknesses.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
PR.AA-03 directly enforces authentication mechanisms that eliminate most improper-authentication defects, yet CWE-287 spans additional vectors (missing checks, flawed protocols, session handling) that one control does not fully close.
PR.AA-04 directly enables verification of identity assertions (mostly preventing CWE-287 in that scope) yet leaves many other authentication failure modes unaddressed (only partial prevention overall).
PR.AA-05 directly enforces policy-based access management and least privilege, eliminating most improper-access-control defects, yet CWE-284 also covers implementation flaws and design gaps outside a single management control.
Hardened baselines and deviation monitoring directly eliminate most configuration-induced access-control defects, yet CWE-284 also encompasses code-level and design flaws outside the scope of configuration management alone.
Secure SDLC practices catch most access-control defects during design/coding/testing (mostly), yet leave residual risk from runtime configuration, architecture, and operational controls (partial).
PR.AA-01 supplies managed identities/credentials that support but do not implement access-control decisions, so it only partially prevents CWE-284 in either direction.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Defining and enforcing explicit access rights and restrictions for each entity directly stops the assignment of permissions that exceed what is required, eliminating the root condition that allows improper access control.
Formal authorization, role-based provisioning, and timely revocation of access rights directly stop the creation of accounts or permissions that exceed what the business actually needs.
By enforcing explicit rules on which identities or groups may perform read, write, delete or execute operations and by denying anonymous access to sensitive data, the control directly stops the creation of overly permissive or missing access-control checks.
Requiring authentication methods whose strength matches the sensitivity of the data and mandating multi-factor authentication directly blocks attempts to access resources without proving identity.
Requiring one-to-one mapping of identities to entities and timely removal of unused identities directly stops attackers from leveraging stale or shared accounts to bypass access restrictions.
Verifying user identity before issuing replacement credentials and forcing changes after compromise reduces the likelihood that authentication bypass can be achieved through stolen or weak credentials.
Hardening callouts derived
Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).
Oracle Linux 8 (3 rules)
- V-248827 OL 8 must not have the rsh-server package installed. prevents CWE-287
- V-248597 There must be no "shosts.equiv" files on the OL 8 operating system. prevents CWE-284
- V-248598 There must be no ".shosts" files on the OL 8 operating system. prevents CWE-284
Oracle Linux 9 (2 rules)
- V-271758 OL 9 file systems must not contain .shosts files. prevents CWE-284
- V-271757 OL 9 file systems must not contain shosts.equiv files. prevents CWE-284
RHEL 7 (5 rules)
- V-204425 The Red Hat Enterprise Linux operating system must be configured so that the SSH daemon does not allow authentication using an empty password. prevents CWE-287
- V-204442 The Red Hat Enterprise Linux operating system must not have the rsh-server package installed. prevents CWE-287
- V-204424 The Red Hat Enterprise Linux operating system must not allow accounts configured with blank or null passwords. prevents CWE-287
RHEL 8 (3 rules)
- V-230492 RHEL 8 must not have the rsh-server package installed. prevents CWE-287
- V-230283 There must be no shosts.equiv files on the RHEL 8 operating system. prevents CWE-284
- V-230284 There must be no .shosts files on the RHEL 8 operating system. prevents CWE-284
Ubuntu 22.04 (1 rule)
- V-260470 Ubuntu 22.04 LTS, when booted, must require authentication upon booting into single-user and maintenance modes. prevents CWE-287
Ubuntu 24.04 (2 rules)
- V-270675 Ubuntu 24.04 LTS when booted must require authentication upon booting into single-user and maintenance modes. prevents CWE-287
- V-270714 Ubuntu 24.04 LTS must not allow accounts configured in Pluggable Authentication Modules (PAM) with blank or null passwords. prevents CWE-287