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.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/zaproxy/zap-extensions/commit/ac6c3f94d38505bc0facea286a4d3728044c6e5c
https://github.com/zaproxy/zap-extensions/pull/7481
https://github.com/zaproxy/zap-extensions/releases/tag/viewstate-v4
https://www.vulncheck.com/advisories/zap-viewstate-add-on-insecure-deserialization-via-jsfviewstate-decode
https://www.zaproxy.org/blog/2026-06-24-java-deserialization-vulnerability-in-zap-viewstate-addon/

Configurations

No configuration.

History

26 Jun 2026, 15:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-26 15:16

Updated : 2026-06-26 17:16

NVD link : CVE-2026-57527

Mitre link : CVE-2026-57527

CVE.ORG link : CVE-2026-57527

JSON object : View

Products Affected

No product.

CWE

CWE-502

Deserialization of Untrusted Data

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