CVE-2020-16844

Exp

In Istio 1.5.0 though 1.5.8 and Istio 1.6.0 through 1.6.7, when users specify an AuthorizationPolicy resource with DENY actions using wildcard suffixes (e.g. *-some-suffix) for source principals or namespace fields, callers will never be denied access, bypassing the intended policy.

Published: 2020-10-01 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2020-16844 is rated High Exploit Risk (60.3/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.28%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2020-16844

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2020-16844

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-04-22 0.16% 0.28% +0.12%
2 2025-03-30 0.46% 0.16% -0.29%
3 2025-03-29 — 0.46% —

Full EPSS history (9 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-16844

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.8 3.1 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 1.6 5.2 [email protected]
4.9 2.0 MEDIUM
AV:N/AC:M/Au:S/C:P/I:P/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
 6.8 4.9 [email protected]

Weakness enumeration for CVE-2020-16844

GitHub Security Advisory for CVE-2020-16844

OS Trackers for CVE-2020-16844

vendor priority summary link
redhat medium — https://access.redhat.com/security/cve/CVE-2020-16844

Affected software / configurations for CVE-2020-16844

Vendor Product Version Raw CPE
istio istio >= 1.5.0, <= 1.5.8 cpe:2.3:a:istio:istio:*:*:*:*:*:*:*:*
istio istio >= 1.6.0, <= 1.6.7 cpe:2.3:a:istio:istio:*:*:*:*:*:*:*:*

References for CVE-2020-16844

cvelogic Threat Intelligence