CVE-2026-14539 (GCVE-0-2026-14539)

Vulnerability from cvelistv5 – Published: 2026-07-31 01:45 – Updated: 2026-07-31 16:11
VLAI
Title
Denial of Service via Unrestricted Payload Buffering in MCP Toolbox
Summary
An allocation of resources without limits vulnerability in the HTTP handler component of Google mcp-toolbox versions up to and including 1.4.0 allows an unauthenticated attacker to cause a denial of service (DoS). The /mcp endpoint handler reads incoming payloads directly into system memory using an unrestricted buffer loop (io.ReadAll) without applying defensive constraints such as http.MaxBytesReader or pre-read Content-Length enforcement. By submitting a single, massive HTTP request body, an attacker can linearly consume available host memory until the runtime process is terminated by an Out-Of-Memory (OOM) error.
Severity
6.6 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-770 - (Allocation of Resources Without Limits or Throttling)
Assigner
References
Impacted products
Vendor Product Version
Google mcp-toolbox Affected: 0.0.0 , ≤ 1.4.0 (semver)
Create a notification for this product.
Credits
HE WEI (ギカク)
Show details on NVD website
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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