SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2025-51986

An issue was discovered in the demo/LINUXTCP implementation of cwalter-at freemodbus v.2018-09-12 allowing attackers to reach an infinite loop via a crafted length value for a packet.

HIGH 7.5EPSS 0.34%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.34%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

An issue was discovered in the demo/LINUXTCP implementation of cwalter-at freemodbus v.2018-09-12 allowing attackers to reach an infinite loop via a crafted length value for a packet.

CVSS 3.1
7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
0.34% probability · 27th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-835
Source
cve@mitre.org
EPSS trend
0%3%5%26 October 2026: 0.34%26 October 202626 October 2026

EPSS 0.3% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.