Apache WSS4J remembers the Nonce of each UsernameToken it accepts, so a captured token cannot be reused. It stored the Nonce as raw base64 text, but authentication decodes that text and uses the bytes.The same bytes can be written as base64 in several ways. An attacker who captured an authenticated request could re-send it with a space added to the Nonce: the password digest still verified, but the token no longer matched the remembered one, so the replay was accepted. Since a UsernameToken does not cover the message body, the captured token could then be reused on requests of the attacker's choosing until it expired. Affects deployments with a nonce replay cache configured, as Apache CXF has by default, and only tokens using a password digest. The cache is now keyed on the decoded Nonce. Users are recommended to upgrade to versions 4.0.2 or 3.0.6 or 2.4.4, which fix this issue.
This vulnerability carries a MEDIUM severity rating with a CVSS v3.1 score of 4.8, indicating it can be exploited remotely over the network but requires specific conditions to be met without requiring user interaction and does not require pre-existing privileges . The vulnerability impacts limited data confidentiality, limited integrity, for affected systems. Impacting 1 product from apache organizations running these solutions should prioritize assessment and patching.
Reported in 2026, this vulnerability emerged during an era marked by increased sophistication in supply chain attacks, cloud infrastructure vulnerabilities, and software-as-a-service (SaaS) security challenges. Security practices during this period emphasized zero-trust architectures, container security, and API protection.
2026-09-30T13:17:21.823
2026-10-02T20:18:52.007
Analyzed
CVSSv3.1: 4.8 (MEDIUM)
| Type | Vendor | Product | Version/Range | Vulnerable? |
|---|---|---|---|---|
| Application | apache | wss4j | < 2.4.4 | Yes |
| Application | apache | wss4j | < 3.0.6 | Yes |
| Application | apache | wss4j | < 4.0.2 | Yes |
SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For apache's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.