{"cve":"CVE-2017-6657","nvd":{"published":"2017-05-16T17:29:00.403","modified":"2026-06-17T01:22:44.603","status":"Modified","description":"Cisco Sourcefire Snort 3.0 before build 233 mishandles Ether Type Validation. Since valid ether type and IP protocol numbers do not overlap, Snort++ stores all protocol decoders in a single array. That makes it possible to craft packets that have IP protocol numbers in the ether type field which will confuse the Snort++ decoder. For example, an eth:llc:snap:icmp6 packet will cause a crash because there is no ip6 header with which to calculate the icmp6 checksum. Affected decoders include gre, llc, trans_bridge, ciscometadata, linux_sll, and token_ring. The fix adds a check in the packet manager to validate the ether type before indexing the decoder array. An out of range ether type will raise 116:473.","cvss_v4":null,"cvss_v3":{"version":"3.0","vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":[],"references":["http://blog.snort.org/2017/05/snort-vulnerabilities-found.html","http://www.securitytracker.com/id/1038483","https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170515-snort","http://blog.snort.org/2017/05/snort-vulnerabilities-found.html","http://www.securitytracker.com/id/1038483"],"products":["cisco:snort\\+\\+"],"source":"nvd","synced_at":"2026-10-19T20:42:36.429588156+00:00"},"epss":{"cve":"CVE-2017-6657","score":0.0106,"percentile":0.64566,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}