Is CVE-2026-88920 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-88920 being exploited in the wild.

How severe is CVE-2026-88920?

Informational severity, published 30 September 2026.

Which products and versions are affected?

Apache WSS4J below 2.4.4, 3.0.x below 3.0.6, 4.0.x below 4.0.2.

Is there a fix for CVE-2026-88920?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-88920 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-88920?

Check whether you run Apache WSS4J at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-88920: Apache WSS4J authentication bypass in DOM security processor

CVE-2026-88920 · Severity: info · Published 2026-09-30

Apache WSS4J is a security library used to process digitally signed SOAP messages in web services. An authentication bypass vulnerability allows attackers to forge authenticated SOAP messages by crafting a malicious unsigned SAML assertion, bypassing signature validation. An attacker could impersonate legitimate users or services, leading to unauthorized access to protected web services and data theft.

Technologies: Apache WSS4J. Vendors: Apache.

Quick answers

Is CVE-2026-88920 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-88920 being exploited in the wild.
How severe is CVE-2026-88920?: Informational severity, published 30 September 2026.
Which products and versions are affected?: Apache WSS4J below 2.4.4, 3.0.x below 3.0.6, 4.0.x below 4.0.2.
Is there a fix for CVE-2026-88920?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-88920 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-88920?: Check whether you run Apache WSS4J at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The DOM security processor in Apache WSS4J fails to properly validate SAML sender-vouches assertions when they contain attacker-controlled keys, allowing signature validation to be bypassed. An unauthenticated remote attacker can craft a malicious unsigned SAML assertion to forge authenticated SOAP messages. This is a network-accessible vulnerability requiring no authentication or user interaction; patches are available in versions 4.0.2, 3.0.6, and 2.4.4.

Affected products

Apache WSS4J below 2.4.4, 3.0.x below 3.0.6, 4.0.x below 4.0.2

Timeline

2026-09-30: disclosed

References

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