RCE in Apache Struts

CVE-2021-31805

The fix issued for CVE-2020-17530 was incomplete. So from Apache Struts 2.0.0 to 2.5.29, still some of the tag’s attributes could perform a double evaluation if a developer applied forced OGNL evaluation by using the %{...} syntax. Using f…

Vulnerability class: Log4Shell (CVE-2021-44228)

EPSS: 0.853 (99.7th 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-2021-31805?
CVE-2021-31805 is a critical-severity vulnerability in Apache Struts, classified under Improper Neutralization of Special Elements used in an Expression Language Statement (Expression Language Injection). CVSS score: 9.8/10. Published 2022-04-12.
How severe is CVE-2021-31805?
Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2021-31805 known to be exploited?
45 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.