CVE WatchJul 14, 2026

CVE-2026-57527

Zed Attack Proxy (ZAP) ViewState add-on before version 4 contains an insecure deserialization vulnerability that allows attackers who contro

CVSS

8.8

High

EPSS

0.5%

p37

KEV

—

Exploit Today

0-100

Published: Jun 26, 2026 · Last modified: Jul 14, 2026 · CWE-502

EPSS · 30d

0.5%EPSS · 30 days0.5%

2026-06-302026-07-17

Technical description

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.

Official references

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