CVE-2019-12243
Istio may not check inbound TCP connections against istio-policy
Istio 1.1.x through 1.1.6 has Incorrect Access Control.
Attack profile
How easy it is to exploit
- Attack vector
- Adjacent network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
Istio 1.1.x through 1.1.6 has Incorrect Access Control.
- Record
CVE-2019-12243- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 5.4 Medium
AV:A/AC:M/Au:N/C:P/I:P/A:P - Updated
- 2026-11-02
CVE List No score
Istio 1.1.x through 1.1.6 has Incorrect Access Control.
- Record
CVE-2019-12243- Updated
- 2026-11-02
EUVDEUVD-2022-0859 No score
Istio 1.1.x through 1.1.6 has Incorrect Access Control.
- Record
EUVD-2022-0859- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-6g5f-f5pm-mjrg
Istio may not check inbound TCP connections against istio-policy
Istio 1.1.x through 1.1.6 has Incorrect Access Control. When disablePolicyChecks is set to false, inbound TCP connections do not generate Check requests to istio-policy and external authorization is not applied.
This behavior is a result of a change to istio/pilot/pkg/networking/plugin/mixer/mixer.go in 1.1.
- Record
GHSA-6g5f-f5pm-mjrg- CVSS 3.1
- 8.9 High
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N/E:H/RL:O/RC:C - Weakness
- CWE-284
- Updated
- 2026-11-02
OSV
Istio 1.1.x through 1.1.6 has Incorrect Access Control.
- Record
CVE-2019-12243- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVGHSA-6g5f-f5pm-mjrg
Istio may not check inbound TCP connections against istio-policy
Istio 1.1.x through 1.1.6 has Incorrect Access Control. When disablePolicyChecks is set to false, inbound TCP connections do not generate Check requests to istio-policy and external authorization is not applied.
This behavior is a result of a change to istio/pilot/pkg/networking/plugin/mixer/mixer.go in 1.1.
- Record
GHSA-6g5f-f5pm-mjrg- CVSS 3.1
- 9.3 Critical
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N/E:H/RL:O/RC:C - Weakness
- CWE-284
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
istio.io/istioGo |
1.1.0 up to 1.1.7 | 1.1.7 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2019-12243 is a high vulnerability (CVSS 7.5) in Istio, published June 5, 2019. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.18%, the 67th percentile. Fixed in istio.io/istio 1.1.7.