CVE-2026-85440
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.
What this means for your business
- An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 1% chance of attack attempts being seen in the next 30 days, ranking above 62% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
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Scoring
- CVSS
- 9.8 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H- CVSS v4
- 9.3
- Weakness
- CWE-787
- Assigned by
- disclosure@vulncheck.com
Dates
- Published
- 2026-09-03
- Last modified
- 2026-09-08
- Sources
- NVD
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