What’s Vulnerable › Vulnerabilities

CVE-2026-85440: MOOS core-moos through 10.4.0 MOOSDB Pre-Authentication Heap Overflow via Negative Packet Length

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.0% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-09-03 · updated 2026-10-14
• Weakness: CWE-787

Description

MOOS core-moos through 10.4.0 contains a pre-authentication heap overflow vulnerability in MOOSCommPkt packet handling that allows remote attackers to write arbitrary data by declaring a negative packet length. Attackers can exploit the signed integer check in InflateTo() and negative size conversion in recv() to overflow a four-byte heap buffer during the HandShake phase before authentication.

Affected products

• themoos core-moos: before 10.4.0 — fixed in 10.4.0

How to fix

Upgrade to a fixed version: themoos core-moos 10.4.0. Check the vendor advisory for mitigations.

References

• https://github.com/themoos/core-moos
• https://github.com/themoos/core-moos/blob/ec9c77c68fcbdef8f5e4c60fe243acd223433f0c/Core/libMOOS/Comms/MOOSCommPkt.cpp#L67
• https://github.com/themoos/core-moos/commit/96c49c5cdda6e07ee734a5324e8d25ba5a7f2d7a
• https://github.com/themoos/core-moos/pull/82
• https://www.vulncheck.com/advisories/moos-core-moos-through-10.4.0-moosdb-pre-authentication-heap-overflow-via-negative-packet-length

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