CVE-2026-85440CWE-787

CVE-2026-85440

Critical · published September 4, 2026

CVSS v3.1
9.8
EPSS
1%
Percentile
63.3
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
9.8 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
9.3 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
EPSS
0.01026 · 63.3th percentile
Weakness
CWE-787 · Out-of-bounds Write
Published
2026-09-04T03:17Z
Affected products (1)
ProductVersionsFixed in
themoos/core-moos< 10.4.010.4.0
References (5)
https://github.com/themoos/core-moos · [email protected]https://github.com/themoos/core-moos/blob/ec9c77c68fcbdef8f5e4c60fe243acd223433f0c/Core/libMOOS/Comms/MOOSCommPkt.cpp#L67 · [email protected]https://github.com/themoos/core-moos/commit/96c49c5cdda6e07ee734a5324e8d25ba5a7f2d7a · [email protected]https://github.com/themoos/core-moos/pull/82 · [email protected]https://www.vulncheck.com/advisories/moos-core-moos-through-10.4.0-moosdb-pre-authentication-heap-overflow-via-negative-packet-length · [email protected]
EPSS history
Timeline
  • 05 SEP 03:44Z
    EPSS moved — → 1%
    epss
  • 03 SEP 22:38Z
    MOOS core-moos through 10.4.0 MOOSDB Pre-Authentication Heap Overflow via Negative Packet Length
    cvelistv5