8.6

CVE-2025-20217: cisco cisco firepower threat defense software Infinite Loop

CVSS: 8.6v3.1HighDeferred
Published 14-08-2025Last modified 14-08-2025
Open JSON

Vulnerability summary

CVE-2025-20217 is a high (CVSS 8.6) Infinite Loop vulnerability in cisco cisco firepower threat defense software. EPSS estimates a 0.72% chance of exploitation in the next 30 days, higher than 52.9% of scored vulnerabilities.

Overall risk
35/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.6/10
010
High · v3.1 (CVE.org)
EPSS score
0.72%
0%100%
Low · +0.03 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 14-08-2025
    PublishedVulnerability first disclosed.
  2. 14-08-2025
    Last modifiedVulnerability information updated.

Description

A vulnerability in the packet inspection functionality of the Snort 3 Detection Engine of Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to incorrect processing of traffic that is inspected by an affected device. An attacker could exploit this vulnerability by sending crafted traffic through the affected device. A successful exploit could allow the attacker to cause the affected device to enter an infinite loop while inspecting traffic, resulting in a DoS condition. The system watchdog will restart the Snort process automatically.

CVSS metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

0.72%

Chance of exploitation in the next 30 days

Percentile

53%

Versus all other CVEs

30-day change

+0.03 pp

From 0.68% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.72%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Cisco1 product
  • cisco firepower threat defense software7.1.0 | 7.1.0.1 | 7.2.0 | 7.1.0.2 | 7.2.0.1 | 7.2.1 | 7.3.0 | 7.2.2 | 7.2.3 | 7.3.1 | 7.1.0.3 | 7.2.4 | 7.2.5 | 7.2.4.1 | 7.3.1.1 | 7.4.0 | 7.2.5.1 | 7.4.1 | 7.2.6 | 7.4.1.1 | 7.2.7 | 7.2.5.2 | 7.3.1.2 | 7.2.8 | 7.6.0 | 7.4.2 | 7.2.8.1 | 7.4.2.1 | 7.2.9

1 vendor · 1 product

References

1 links