Multiple Cisco Products Snort Modbus Denial of Service Vulnerability

published 2024-11-15 last yr. modified 2026-08-11 2mo ago also EUVD-2022-25935

cvss: 7.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.5%; EPSS 1.5% chance of exploitation in 30 days, percentile 73%
public exploits: 0; none known

A vulnerability in the Modbus preprocessor of the Snort detection engine could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to an integer overflow while processing Modbus traffic. An attacker could exploit this vulnerability by sending crafted Modbus traffic through an affected device. A successful exploit could allow the attacker to cause the Snort process to hang, causing traffic inspection to stop.Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

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CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: last yr. (2024-11-15)

Exploit prediction

1.46% chance of exploitation in the next 30 days, higher than 73% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CISA ADP	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

Cisco Cisco Cyber Vision
Cisco Cisco Firepower Threat Defense Software
Cisco Cisco UTD SNORT IPS Engine Software

Classification

Weakness

CWE-190 Integer Overflow or Wraparound

References

Sources

CVE List CVE-2022-20685
NVD CVE-2022-20685

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