PT-2021-3729 · Red Hat · Openshift

Przemyslaw Roguski · CVE-2021-3636 · Published 2021-07-28 · Updated 2022-10-27

Positive Technologies (AI Summary)

CVSS v2.0

6.8

Medium

Base vector

AV:N/AC:L/Au:S/C:N/I:C/A:N

Name of the Vulnerable Software and Affected Versions OpenShift versions prior to 4.8

Description The issue is related to the generated certificate for the in-cluster Service CA in OpenShift, which incorrectly includes additional certificates. This allows an attacker that compromises any of the additional CAs to masquerade as a trusted in-cluster service. The Service CA is automatically mounted into all pods, enabling them to connect to trusted in-cluster services that present certificates signed by the trusted Service CA.

Recommendations For versions prior to 4.8, update to version 4.8 or later to resolve the issue. As a temporary workaround, consider restricting access to the Service CA to minimize the risk of exploitation.

Exploit

Fix

Improper Authentication

Improper Certificate Validation

Weakness Enumeration

CWE-287

CWE-295

Related Identifiers

BDU:2021-03969

CVE-2021-3636

RHSA-2021:2437

Affected Products

Openshift

References · 7

• 🔥 https://bugzilla.redhat.com/show_bug.cgi?id=1978621 · Exploit
• https://osv.dev/vulnerability/CVE-2021-3636 · Vendor Advisory
• https://bdu.fstec.ru/vul/2021-03969 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2021-3636 · Security Note
• https://t.me/cvenotify/18382 · Telegram Post
• https://packetstormsecurity.com/files/cve/CVE-2021-3636 · Note
• https://access.redhat.com/security/cve/cve-2021-3636 · Note