CVE-2026-57527
Zed Attack Proxy (ZAP) ViewState add-on before version 4 contains an insecure deserialization vulnerability that allows attackers who control a proxied web server to achieve arbitrary code execution by embedding a malicious serialized Java object in the javax.faces.ViewState HTTP response parameter. The JSFViewState.decode() method base64-decodes the ViewState value and passes it directly to ObjectInputStream.readObject() without a deserialization filter, allowlist, or type restriction, causing the malicious object to be deserialized within the ZAP JVM when the Desktop UI renders the ViewState panel.
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Exploitation outlook
- Low exploitation risk0.46% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 37% of all EPSS-scored CVEs.
Advisory coverage (1)
External references
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