XXE in Owasp Json-Sanitizer

CVE-2021-23899

OWASP json-sanitizer before 1.2.2 may emit closing SCRIPT tags and CDATA section delimiters for crafted input. This allows an attacker to inject arbitrary HTML or XML into embedding documents.

Vulnerability class: XXE (XML External Entity)

EPSS: 0.021 (79.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-23899?
CVE-2021-23899 is a critical-severity vulnerability in Owasp Json-Sanitizer, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 9.8/10. Published 2021-01-13.
How severe is CVE-2021-23899?
Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2021-23899 known to be exploited?
6 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.