VulnerabilityUndergoing Analysis

CVE-2026-59279

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.

HIGH 7.5EPSS 0.39%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.39%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

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

CVSS 3.1: 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS: 0.39% probability · 32th percentile
CISA KEV: Not listed
Weakness: CWE-770
Source: security@vmware.com

References

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

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.