Vulnerability Name:

CVE-2021-31921 (CCN-202963)

Assigned:2021-05-11
Published:2021-05-11
Updated:2022-05-01
Summary:Istio before 1.8.6 and 1.9.x before 1.9.5 contains a remotely exploitable vulnerability where an external client can access unexpected services in the cluster, bypassing authorization checks, when a gateway is configured with AUTO_PASSTHROUGH routing configuration.
CVSS v3 Severity:9.8 Critical (CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)
8.5 High (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): High
Integrity (I): High
Availibility (A): High
10.0 Critical (CCN CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H)
8.7 High (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope:Scope (S): Changed
Impact Metrics:Confidentiality (C): High
Integrity (I): High
Availibility (A): High
CVSS v2 Severity:6.8 Medium (CVSS v2 Vector: AV:N/AC:M/Au:N/C:P/I:P/A:P)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Medium
Authentication (Au): None
Impact Metrics:Confidentiality (C): Partial
Integrity (I): Partial
Availibility (A): Partial
10.0 High (CCN CVSS v2 Vector: AV:N/AC:L/Au:N/C:C/I:C/A:C)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Low
Athentication (Au): None
Impact Metrics:Confidentiality (C): Complete
Integrity (I): Complete
Availibility (A): Complete
Vulnerability Type:CWE-862
Vulnerability Consequences:Bypass Security
References:Source: MITRE
Type: CNA
CVE-2021-31921

Source: XF
Type: UNKNOWN
istio-cve202131921-sec-bypass(202963)

Source: CCN
Type: ISTIO-SECURITY-2021-006
Istio

Source: MISC
Type: Exploit, Vendor Advisory
https://istio.io/latest/news/security/istio-security-2021-006/

Vulnerable Configuration:Configuration 1:
  • cpe:/a:istio:istio:*:*:*:*:*:*:*:* (Version < 1.8.6)
  • OR cpe:/a:istio:istio:*:*:*:*:*:*:*:* (Version >= 1.9.0 and < 1.9.5)

    • Configuration CCN 1:
  • cpe:/a:istio:istio:1.8.0:-:*:*:*:*:*:*
  • OR cpe:/a:istio:istio:1.9.0:-:*:*:*:*:*:*

    • * Denotes that component is vulnerable
    BACK
    istio istio *
    istio istio *
    istio istio 1.8.0 -
    istio istio 1.9.0 -