Vulnerability Name:

CVE-2021-39156 (CCN-208204)

Assigned:2021-08-24
Published:2021-08-24
Updated:2022-08-12
Summary:Istio is an open source platform for providing a uniform way to integrate microservices, manage traffic flow across microservices, enforce policies and aggregate telemetry data. Istio 1.11.0, 1.10.3 and below, and 1.9.7 and below contain a remotely exploitable vulnerability where an HTTP request with `#fragment` in the path may bypass Istio’s URI path based authorization policies. Patches are available in Istio 1.11.1, Istio 1.10.4 and Istio 1.9.8. As a work around a Lua filter may be written to normalize the path.
CVSS v3 Severity:7.5 High (CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N)
6.5 Medium (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/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): None
Availibility (A): None
8.1 High (CCN CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N)
7.1 High (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): Required
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): High
Integrity (I): High
Availibility (A): None
CVSS v2 Severity:5.0 Medium (CVSS v2 Vector: AV:N/AC:L/Au:N/C:P/I:N/A:N)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Low
Authentication (Au): None
Impact Metrics:Confidentiality (C): Partial
Integrity (I): None
Availibility (A): None
8.5 High (CCN CVSS v2 Vector: AV:N/AC:L/Au:S/C:C/I:C/A:N)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Low
Athentication (Au): Single_Instance
Impact Metrics:Confidentiality (C): Complete
Integrity (I): Complete
Availibility (A): None
Vulnerability Type:CWE-706
Vulnerability Consequences:Bypass Security
References:Source: MITRE
Type: CNA
CVE-2021-39156

Source: XF
Type: UNKNOWN
istio-cve202139156-sec-bypass(208204)

Source: CCN
Type: Istio GIT Repository
Fragments in Path May Lead to Authorization Policy Bypass

Source: CONFIRM
Type: Third Party Advisory
https://github.com/istio/istio/security/advisories/GHSA-hqxw-mm44-gc4r

Source: MISC
Type: Vendor Advisory
https://istio.io/latest/news/security/istio-security-2021-008

Source: CCN
Type: WhiteSource Vulnerability Database
CVE-2021-39156

Vulnerable Configuration:Configuration 1:
  • cpe:/a:istio:istio:*:*:*:*:*:*:*:* (Version >= 1.11.0 and < 1.11.1)
  • OR cpe:/a:istio:istio:*:*:*:*:*:*:*:* (Version < 1.9.8)
  • OR cpe:/a:istio:istio:*:*:*:*:*:*:*:* (Version >= 1.10.0 and < 1.10.3)

    • Configuration CCN 1:
  • cpe:/a:istio:istio:1.9.0:-:*:*:*:*:*:*
  • OR cpe:/a:istio:istio:1.10.0:-:*:*:*:*:*:*
  • OR cpe:/a:istio:istio:1.11.0:-:*:*:*:*:*:*

    • * Denotes that component is vulnerable
    BACK
    istio istio *
    istio istio *
    istio istio *
    istio istio 1.9.0 -
    istio istio 1.10.0 -
    istio istio 1.11.0 -