# CVE-2026-103761 — kvcache-ai Mooncake

> As of 2026-10-01, CVE-2026-103761 is a HIGH-severity vulnerability in kvcache-ai Mooncake, CVSS v3.1 7.5, EPSS 0.3% (28.1th percentile). No Threadlinqs-tracked threat campaign has been attributed to CVE-2026-103761 as of 2026-10-01; the identifier is re-checked against the Threadlinqs threat corpus on every daily ingest.

**Last updated:** 2026-10-01

## What is CVE-2026-103761?

Mooncake transfer engine through 0.3.13.post1 contains a memory exhaustion vulnerability in TransferMetadata::receivePeerNotify that allows unauthenticated attackers to grow process memory without limit. Attackers can repeatedly send notify frames up to 1 MB to the handshake RPC port, filling the uncapped notifys vector until the out-of-memory killer terminates the engine.

The record classifies CVE-2026-103761 under weakness class [CWE-770](https://intel.threadlinqs.com/cwe/CWE-770). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs no user interaction, and has high impact on availability. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 4 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 7.5 — HIGH (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **CVSS v4.0 base score:** 8.7 (`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`)
- **EPSS (FIRST):** 0.3% probability of exploitation in the next 30 days, higher than 28.1% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 6.9/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-10-01

## Is CVE-2026-103761 being exploited?

Weaponised exploit code for CVE-2026-103761 is publicly available. 1 public proof-of-concept repository is tracked for this identifier. It currently carries a trending score of 44 in the Threadlinqs vulnerability feed.

- [trickest/cve](https://github.com/trickest/cve/blob/main/2026/CVE-2026-103761.md) (trickest)

## Affected products and versions

- **kvcache-ai**: Mooncake

## How to fix CVE-2026-103761

No vendor patch reference has been recorded for CVE-2026-103761 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2026-103761

No threat campaign in the Threadlinqs corpus currently references CVE-2026-103761, in its CVE list or as an indicator. The linkage is recomputed from the live corpus on every daily ingest, so this section fills in as soon as a tracked campaign cites the identifier.

## Sources

Enriched from CVE.org, NVD, FIRST EPSS, GitHub Security Advisories, public proof-of-concept repositories. Last verified by Threadlinqs on 2026-10-04. This product uses the NVD API but is not endorsed or certified by the NVD.

**Technical analysis**

- [github.com — technical description](https://github.com/kvcache-ai/Mooncake/blob/719735896c86b56fabec6cf3e825fb2ea640597a/mooncake-transfer-engine/src/transfer_metadata.cpp#L285-L296)

**Third-party advisory**

- [vulncheck.com — third party advisory](https://www.vulncheck.com/advisories/mooncake-transfer-engine-through-0.3.13-post1-memory-exhaustion-via-unbounded-notify-queue)

**Issue tracking and product pages**

- [github.com — issue tracking](https://github.com/kvcache-ai/Mooncake/issues/4445)
- [github.com — product](https://github.com/kvcache-ai/Mooncake)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-103761
Full detection coverage and IOCs for threats exploiting CVE-2026-103761 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp