CVE-2026-59279 — Unbounded persistent session allocation via repeated initialize requests

CVE-2026-59279

Unbounded persistent session allocation via repeated initialize requests PUBLISHED

Description (CNA)

The MCP Streamable HTTP server transport (WebFlux and WebMvc variants) does not place any limit on the number of sessions it retains, and by default does not require clients to be authenticated. As a result, a remote attacker can cause the server to accumulate an unbounded number of sessions over time, gradually exhausting available memory and ultimately causing a Denial of Service that affects all legitimate clients. Affected versions: Spring AI: 2.0.0

Affected (CNA)

Vendor / product	Versions
Spring / Spring AI	affected 2.0.0

CWE

CWE-770

References

https://spring.io/security/cve-2026-59279

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.