CVE-2022-3867 in Nomad
Summary
by MITRE • 11/10/2022
HashiCorp Nomad and Nomad Enterprise 1.4.0 up to 1.4.1 event stream subscribers using a token with TTL receive updates until token garbage is collected. Fixed in 1.4.2.
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Analysis
by VulDB Data Team • 11/11/2022
The vulnerability identified as CVE-2022-3867 affects HashiCorp Nomad and Nomad Enterprise versions 1.4.0 through 1.4.1, specifically impacting event stream subscribers that utilize tokens with time-to-live expiration settings. This issue represents a security flaw in the token management and session handling mechanisms of the Nomad orchestration platform, which could potentially allow unauthorized access to event streams beyond the intended token expiration period.
The technical flaw stems from improper token lifecycle management within the event stream subscription system. When users establish event stream subscriptions using tokens that are configured with TTL values, the system fails to immediately terminate the subscription upon token expiration. Instead, these subscriptions continue to receive updates until the token undergoes garbage collection, creating an extended window of potential unauthorized access. This behavior violates fundamental security principles of token-based authentication and session management, as the system does not enforce immediate revocation of access rights upon token expiration.
The operational impact of this vulnerability extends beyond simple access control concerns, as it could enable attackers to maintain persistent access to sensitive event stream data within Nomad clusters. Attackers who obtain valid tokens with TTL settings could potentially exploit this vulnerability to continue receiving updates from event streams even after the original token expiration time has passed, providing them with extended visibility into cluster activities and potentially sensitive operational data. This could compromise the integrity of the event stream monitoring system and provide attackers with valuable information for further exploitation attempts.
This vulnerability aligns with CWE-613, which addresses insufficient session expiration, and relates to ATT&CK technique T1567.002 for "Exfiltration Over Web Service" and T1078.004 for "Valid Accounts" as it involves the improper handling of authenticated sessions. The flaw represents a failure in proper access control enforcement and session management, creating a window of opportunity for unauthorized access that extends beyond the intended token lifespan.
The fix implemented in version 1.4.2 addresses this issue by ensuring that event stream subscriptions are properly terminated immediately upon token expiration, rather than waiting for garbage collection. This update enforces proper token lifecycle management and ensures that access to event streams is revoked promptly when tokens expire, thereby preventing the extended access window that previously existed. Organizations using affected versions should immediately upgrade to 1.4.2 or later to mitigate this vulnerability and maintain proper security boundaries within their Nomad environments.