Auth bypass in Cncf Spire
CVE-2021-27099
In SPIRE before versions 0.8.5, 0.9.4, 0.10.2, 0.11.3 and 0.12.1, the "aws_iid" Node Attestor improperly normalizes the path provided through the agent ID templating feature, which may allow the issuance of an arbitrary SPIFFE ID within the same trust domain, if the attacker controls the value of an EC2 tag prior to attestation, and the attestor is configured for agent ID templating where the tag value is the last element in the path. This issue has been fixed in SPIRE versions 0.11.3 and 0.12.1
Vulnerability class: Broken Access Control
EPSS: 0.007 (50.2th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.8 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N.
Affected products
- Cncf Spire
- N/a — versions n/a
Weakness classification (CWE)
References
- cve@mitre.org (Patch, Third Party Advisory, x_refsource_MISC)
Frequently asked questions
- What is CVE-2021-27099?
- CVE-2021-27099 is a medium-severity vulnerability in Cncf Spire, classified under Incorrect Authorization. CVSS score: 6.8/10. Published 2021-03-05.
- How severe is CVE-2021-27099?
- Medium severity. CVSS v3 base score is 6.8 out of 10.