CVE-2026-108088 in Cocoon
Summary
by MITRE • 10/20/2026
** UNSUPPORTED WHEN ASSIGNED ** Use of cache containing sensitive information vulnerability in Apache Cocoon. When using the cache on a multi-user application, cached values for one user could be used when serving content for other users.
This issue affects Apache Cocoon: all versions.
As this project is retired, we do not plan to release a version that fixes this issue. Users are recommended to find an alternative or restrict access to the instance to trusted users.
NOTE: This vulnerability only affects products that are no longer supported by the maintainer.
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Analysis
by VulDB Data Team • 10/20/2026
The identified vulnerability in Apache Cocoon represents a critical failure in session isolation within its caching mechanism, specifically classified under CWE-200 as an Information Exposure issue and aligning with MITRE ATT&CK technique T1530 which involves data exfiltration from local system storage. This flaw emerges when the application utilizes a cache to store processed content or sensitive user-specific data for performance optimization on multi-user systems. In a properly secured environment, cached items must be strictly bound to the specific session or user context that generated them. However, due to this architectural oversight, the caching logic fails to enforce adequate separation between different users' sessions. Consequently, when User A requests content that is not yet in the cache, Cocoon generates it and stores it. If User B subsequently makes a request for similar content before the cache entry expires or is invalidated by proper session boundaries, the system may serve the cached response intended for User A to User B. This cross-user data leakage occurs because the cache key does sufficiently incorporate unique user identifiers such as session tokens or authentication contexts, leading to a scenario where sensitive information belonging to one individual becomes accessible to another without authorization.
The operational impact of this vulnerability is severe in any deployment context involving multiple concurrent users accessing protected resources. Attackers can exploit this flaw to perform unauthorized data access, effectively bypassing application-level security controls that rely on session management for isolation. By repeatedly querying the server and analyzing responses or timing differences, an adversary could potentially reconstruct sensitive documents, personal identifiable information, or internal business logic intended for other users. This undermines the confidentiality integrity of the entire web application stack. Since Apache Cocoon is a legacy framework primarily used in older enterprise content management systems, many deployments may still be running on outdated infrastructure with limited monitoring capabilities, making such attacks difficult to detect in real-time. The lack of explicit error messages or access denied responses when serving incorrect cached data further aids attackers in confirming successful exploitation through side-channel analysis rather than direct feedback from the application.
Given that Apache Cocoon is officially retired and no patches are planned by the maintainers, remediation strategies must focus on architectural changes and compensating controls rather than software updates. The most effective mitigation is to migrate legacy applications to a supported modern framework or content management system that adheres to current security standards for session handling and caching. For organizations unable to immediately replace the underlying technology, restricting access to trusted users through robust network-level firewalls and strict identity verification at the perimeter can reduce the attack surface significantly. Additionally implementing application-layer controls such as disabling aggressive caching for sensitive endpoints or ensuring cache keys include unique per-session identifiers like CSRF tokens or session IDs can mitigate the risk within existing deployments. It is also advisable to review logging mechanisms to detect anomalous patterns of access that might indicate exploitation attempts, although this serves primarily as a detection measure rather than a prevention strategy. Ultimately, relying on unsupported software with known critical flaws poses an unacceptable risk profile for any production environment handling sensitive data.