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CVE-2026-20066

Multiple Cisco Products Snort 3 TBD Denial of Service Vulnerability PUBLISHED

Description (CNA)

Multiple Cisco products are affected by a vulnerability in the Snort 3 Detection Engine that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to restart, resulting in an interruption of packet inspection. This vulnerability is due to an error in the JSTokenizer normalization logic when the HTTP inspection normalizes JavaScript. An attacker could exploit this vulnerability by sending crafted HTTP packets through an established connection that is parsed by Snort 3. A successful exploit could allow the attacker to cause a DoS condition when the Snort 3 Detection Engine restarts unexpectedly. JSTokenizer is not enabled by default.

Affected (CNA)

Vendor / productVersions
Cisco / Cisco Secure Firewall Threat Defense (FTD) Softwareaffected 7.4.0; affected 7.4.1; affected 7.4.1.1; affected 7.6.0; affected 7.4.2; affected 7.4.2.1; affected 7.7.0; affected 7.4.2.2; affected 7.6.1; affected 7.4.2.3; affected 7.6.2; affected 7.7.10; affected 7.6.2.1; affected 7.7.10.1; affected 7.4.2.4; affected 7.4.3
Cisco / Cisco UTD SNORT IPS Engine Softwareaffected 17.3.1a; affected 17.2.1r; affected 17.3.2; affected 17.4.1a; affected 17.5.1; affected 17.3.3; affected 17.5.1a; affected 17.3.4; affected 17.3.4a; affected 17.4.2; affected 17.4.1b; affected 17.6.1a; affected 17.7.1a; affected 17.6.2; affected 17.8.1a; affected 17.3.5; affected 17.6.3; affected 17.6.3a; affected 17.7.2; affected 17.9.1a; affected 17.6.4; affected 17.10.1a; affected 17.3.6; affected 17.3.7; affected 17.9.2a; affected 17.6.5; affected 17.11.1a; affected 17.9.3a; affected 17.12.1a; affected 17.9.4; affected 17.6.6; affected 17.3.8; affected 17.3.8a; affected 17.6.6a; affected 17.9.4a; affected 17.12.2; affected 17.13.1a; affected 17.9.5a; affected 17.12.3; affected 17.6.7; affected 17.14.1a; affected 17.12.4; affected 17.12.3a; affected 17.15.1a; affected 17.6.8; affected 17.9.6; affected 17.6.8a; affected 17.16.1a; affected 17.9.5e; affected 17.12.4a; affected 17.15.2c; affected 17.9.5f; affected 17.12.4b; affected 17.15.2a; affected 17.12.5; affected 17.17.1; affected 17.12.5a; affected 17.9.7a; affected 17.15.3a; affected 17.15.3; affected 17.12.5b; affected 17.12.5c; affected 17.15.4; affected 17.9.7b; affected 17.18.1; affected 17.18.1a; affected 17.12.6; affected 17.9.8; affected 17.15.4c; affected 17.12.5d; affected 17.18.2

CWE

CWE-400

References

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.