zaproxy zap-extensions up to 3 JSFViewState.decode ViewState deserialization

CVSS Meta Temp Score
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CTI Interest Score
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7.4$0-$5k0.00-

Summaryinfo

A vulnerability described as critical has been identified in zaproxy zap-extensions up to 3. This impacts the function JSFViewState.decode. Executing a manipulation of the argument ViewState can lead to deserialization. This vulnerability appears as CVE-2026-57527. The attack may be performed from remote. There is no available exploit. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in zaproxy zap-extensions up to 3. It has been declared as critical. This vulnerability affects the function JSFViewState.decode. The manipulation of the argument ViewState with an unknown input leads to a deserialization vulnerability. The CWE definition for the vulnerability is CWE-502. The product deserializes untrusted data without sufficiently verifying that the resulting data will be valid. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

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.

The weakness was presented by Neo. The advisory is available at zaproxy.org. This vulnerability was named CVE-2026-57527 since 06/24/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Successful exploitation requires user interaction by the victim. Technical details are known, but there is no available exploit.

Upgrading to version 4 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch ac6c3f94d38505bc0facea286a4d3728044c6e5c is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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Vendor

Name

Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 7.6
VulDB Meta Temp Score: 7.4

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 8.8
CNA Vector (VulnCheck): 🔒

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Deserialization
CWE: CWE-502 / CWE-20
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: zap-extensions 4
Patch: ac6c3f94d38505bc0facea286a4d3728044c6e5c

Timelineinfo

06/24/2026 CVE reserved
06/26/2026 +2 days Advisory disclosed
06/26/2026 +0 days VulDB entry created
06/26/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: zaproxy.org
Researcher: Neo
Status: Confirmed

CVE: CVE-2026-57527 (🔒)
GCVE (CVE): GCVE-0-2026-57527
GCVE (VulDB): GCVE-100-374218

Entryinfo

Created: 06/26/2026 18:56
Changes: 06/26/2026 18:56 (81)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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