Description
Asymmetric resource consumption (amplification) vulnerability in Apache Struts. When a request parameter is bound to an arbitrary-precision decimal (java.math.BigDecimal) property that is then rendered through the Struts tag library, the framework can produce a response many orders of magnitude larger than the request, allowing an unauthenticated remote attacker to exhaust server CPU and outbound network capacity with sustained low-volume traffic. Applications that do not bind request parameters to BigDecimal properties, or never render such a property through the Struts tag library, are not affected. This issue affects Apache Struts: from 2.5.14 through 2.5.33, from 6.0.0 through 6.11.0, from 7.0.0 through 7.3.0. Users are recommended to upgrade to version 6.12.0 or 7.4.0, which fixes the issue.
Affected products
apache: struts
References2
- cwiki.apache.org/confluence/display/WW/S2-076 Vendor Advisory
- www.openwall.com/lists/oss-security/2026/10/05/11 Mailing ListThird Party Advisory
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 1% percentile: 58 · as of 10 November 2026
- CWE
- CWE-405
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