CVE-2020-8196Citrix ADC, Gateway, and SD-WAN WANOP Appliance Information Disclosure Vulnerability
CVE-2020-8196 is a improper authentication in Citrix Application Delivery Controller (ADC), Gateway, and SD-WAN WANOP Appliance, rated medium (4.3 on CVSS 3.1).
Why this priority: Exploited in the wild: listed in CISA's KEV catalog.
Published · Updated · NVD status: Analyzed
What it is
The software does not prove who a caller is, so an attacker can pass as someone else. Access to a resource or action is not restricted to the people meant to have it.
How it is reached
An attacker can exploit it over the network, with an ordinary user account, and nobody has to click anything.
What an attacker gains
The direct impact is limited: partial access to data or a partial outage. In practice, this kind of flaw lets an attacker act as a signed-in user, or an administrator, without valid credentials.
Is it being exploited?
CISA added it to the Known Exploited Vulnerabilities catalog on 2021-11-03: it is being exploited in the wild. EPSS estimates a 26% chance of exploitation activity in the next 30 days, higher than 98% of scored CVEs.
What to do
- Treat it as urgent: it is on CISA's KEV list. CISA's deadline for US federal agencies: 2022-05-03.
- Upgrade Citrix Application Delivery Controller (ADC), Gateway, and SD-WAN WANOP Appliance to a fixed version for your release line (10.2.7, 11.0.3d, 11.1.1a). Other affected products have their own fixed versions on this page.
- Until it is patched, review who holds accounts that can reach it.
- Check exposed instances for signs of compromise, not only for the version.
Description from NVD
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.
What this means for your architecture.
A CVE names a product. Whether it matters depends on where that product sits in your systems: what reaches it, which trust boundary it guards and what it can reach once compromised. Veriom maps your components, their relationships and your trust boundaries from your code, cloud and delivery evidence, so you can see where a component like this sits. The radar itself does not look at your systems.
Components it touches
- Network edge devices: VPNs, firewalls, routers and gateways. They sit between the internet and internal networks, so a flaw in one is often the first step into everything behind it.
- Operating systems on servers, workstations or devices. Everything on the host inherits the flaw.
- Sign-in, session and token handling. The flaw sits between anonymous callers and authenticated sessions.
- Identity providers and SSO. The flaw sits between anonymous callers and authenticated sessions.
Trust boundaries in play
- Authenticated network access. An account is needed, so exposure follows who can sign in: customers, partners or staff.
- Between anonymous callers and authenticated sessions. An attacker who crosses it can act as a signed-in user, or an administrator, without valid credentials.
- Between one role or tenant and another. An attacker who crosses it can reach data or actions their role should not allow.
Questions to answer about your own systems
- Where does Citrix Application Delivery Controller (ADC), Gateway, and SD-WAN WANOP Appliance run in your systems, and at which version?
- Which of those instances can be reached from the internet or partner networks?
- What can it reach once compromised: which data stores, secrets and services?
Sources
- CVE records and CVSS scores from the NVD CVE API. This product uses the NVD API but is not endorsed or certified by the NVD.
- Exploitation status from CISA’s Known Exploited Vulnerabilities catalog.
- Exploit likelihood from FIRST’s Exploit Prediction Scoring System (EPSS), refreshed daily.
- Explanations are written by Veriom from fixed templates over each record’s data, not by a person reviewing each CVE. Descriptions are quoted from the records as published.