XXE in Fusionauth Saml V2
CVE-2021-27736
FusionAuth fusionauth-samlv2 before 0.5.4 allows XXE attacks via a forged AuthnRequest or LogoutRequest because parseFromBytes uses javax.xml.parsers.DocumentBuilderFactory unsafely.
Vulnerability class: XXE (XML External Entity)
EPSS: 0.013 (67.1th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.
Affected products
- Fusionauth Saml_v2
- N/a — versions n/a
Weakness classification (CWE)
Public proof-of-concept exploits
References
- cve@mitre.org (Patch, Third Party Advisory, x_refsource_MISC)
- cve@mitre.org (Patch, Third Party Advisory, x_refsource_MISC)
- cve@mitre.org (Exploit, Third Party Advisory, x_refsource_MISC)
Frequently asked questions
- What is CVE-2021-27736?
- CVE-2021-27736 is a medium-severity vulnerability in Fusionauth Saml V2, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 6.5/10. Published 2021-04-22.
- How severe is CVE-2021-27736?
- Medium severity. CVSS v3 base score is 6.5 out of 10.
- Is CVE-2021-27736 known to be exploited?
- 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.