{"id":"CVE-2017-6657","aliases":["EUVD-2017-15711","GHSA-h9jm-vc47-2v23"],"status":"published","title":"Cisco Sourcefire Snort 3.0 before build 233 mishandles Ether Type Validation. Since valid ether...","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.","severity":{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-08","score":0.0106,"percentile":0.64779,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"published":"2017-05-16T17:00:00Z","modified":"2026-06-17T01:22:44Z","products":[{"vendor":"cisco","product":"snort\\+\\+"}],"references":[{"url":"http://www.securitytracker.com/id/1038483","tags":["vdb-entry","x_refsource_SECTRACK","x_transferred"]},{"url":"http://blog.snort.org/2017/05/snort-vulnerabilities-found.html","tags":["x_refsource_CONFIRM","x_transferred","Third Party Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2017-6657"},{"url":"https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170515-snort","tags":["Vendor Advisory"]},{"url":"https://github.com/advisories/GHSA-h9jm-vc47-2v23"}],"sources":{"cve":[{"id":"CVE-2017-6657","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.","status":"published","published":"2017-05-16T17:00:00Z","modified":"2024-08-05T15:33:20.453Z","updated_at":"2026-11-02T14:33:16.916541Z"}],"euvd":[{"id":"EUVD-2017-15711","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.","status":"published","published":"2017-05-16T17:00:00Z","modified":"2024-08-05T15:33:20Z","updated_at":"2026-11-03T02:39:11.589017Z"}],"ghsa":[{"id":"GHSA-h9jm-vc47-2v23","title":"Cisco Sourcefire Snort 3.0 before build 233 mishandles Ether Type Validation. Since valid ether...","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.","status":"published","published":"2022-05-13T01:46:42Z","modified":"2023-02-02T05:01:26Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-02T14:51:11.302625Z"}],"nvd":[{"id":"CVE-2017-6657","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.","status":"published","published":"2017-05-16T17:29:00.403Z","modified":"2026-06-17T01:22:44.603Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary"},{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:N/I:N/A:P","level":"medium","assessor":"primary"}],"updated_at":"2026-11-02T14:03:47.848196Z"}]}}