{"id":"CVE-2023-20109","kind":"vulnerability","aliases":["CVE-2023-20109"],"related":[],"title":"A vulnerability in the Cisco Group Encrypted Transport VPN (GET VPN) feature of Cisco IOS Software and Cisco IOS XE…","description":"A vulnerability in the Cisco Group Encrypted Transport VPN (GET VPN) feature of Cisco IOS Software and Cisco IOS XE Software could allow an authenticated, remote attacker who has administrative control of either a group member or a key server to execute arbitrary code on an affected device or cause the device to crash.\r\n\r This vulnerability is due to insufficient validation of attributes in the Group Domain of Interpretation (GDOI) and G-IKEv2 protocols of the GET VPN feature. An attacker could exploit this vulnerability by either compromising an installed key server or modifying the configuration of a group member to point to a key server that is controlled by the attacker. A successful exploit could allow the attacker to execute arbitrary code and gain full control of the affected system or cause the affected system to reload, resulting in a denial of service (DoS) condition. For more information, see the Details [\"#details\"] section of this advisory.","summary":"Cisco IOS and IOS XE have an out-of-bounds write in the Group Encrypted Transport VPN (GET VPN) feature. An attacker with administrative control of a GET VPN group member or key server can run malicious code on the device or crash it.","severity":"high","cvss":6.6,"epss":null,"exploited":true,"exploited_at":"2023-10-10T00:00:00+00:00","products":[{"name":"Cisco IOS and IOS XE","fixed":[],"affected":"","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)md","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)md1","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)md2","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)mda","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)mda1","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)mda2","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)mda3","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)mda4","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)mda5","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)mda6","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)t","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)t1","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)t2","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)t3","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)t4","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)t5","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)xr1","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)xr2","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)xr3","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)xr4","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)xr5","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)xr6","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)xr7","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)xr8","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)xr9","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)xr10","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)xr11","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(22\\)xr12","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(24\\)md","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(24\\)md1","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(24\\)md2","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(24\\)md3","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(24\\)md4","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(24\\)md5","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(24\\)md6","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(24\\)md7","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(24\\)mda1","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(24\\)mda2","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(24\\)mda3","ecosystem":"vendor"},{"name":"cisco ios","fixed":[],"affected":"= 12.4\\(24\\)mda4","ecosystem":"vendor"}],"ecosystems":["vendor"],"tags":["cisco","exploited","get-vpn","infrastructure","ios","ios-xe","network-appliance"],"not_affected_if":["default-config","no-get-vpn"],"how_to_check":null,"fix":"Apply the mitigation from Cisco's vendor advisory, or stop using the affected product if no mitigation exists (per CISA required action). Fixed versions: unknown","status":"open","published_at":"2023-09-27T18:15:10+00:00","first_seen_at":"2026-10-23T19:11:51+00:00","triaged_at":"2026-10-23T21:04:26+00:00","updated_at":"2026-10-23T22:29:04+00:00","category":"infrastructure","confidence":0.7,"triage":{"at":"2026-10-23T21:04:26Z","model":"claude-haiku-5-5","output":{"fix":"Apply the mitigation from Cisco's vendor advisory, or stop using the affected product if no mitigation exists (per CISA required action). Fixed versions: unknown","reach":"network","impact":"high","summary":"Cisco IOS and IOS XE have an out-of-bounds write in the Group Encrypted Transport VPN (GET VPN) feature. An attacker with administrative control of a GET VPN group member or key server can run malicious code on the device or crash it.","category":"infrastructure","who_cares":["cisco","ios","ios-xe","network-appliance","get-vpn"],"confidence":0.7,"needs_auth":"yes","worst_case":"Attacker runs malicious code on the router or switch, or crashes it","analyst_note":"Find the Cisco advisory for CVE-2023-20109 to get affected and fixed IOS/IOS XE versions and the GET VPN mitigation steps; the KEV entry alone does not give them.","how_to_check":"unknown","needs_analyst":true,"not_affected_if":["no-get-vpn","default-config"],"user_interaction":"no","needs_special_setup":"yes","severity_if_unknown":"high"},"cost_usd":0.000491,"input_tokens":2889,"output_tokens":405,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-20109':23A,26A '-2023':22A,25A 'administr':149B,198C 'advisori':326C 'affect':215C,299C,304C 'allow':191C,286C 'and':29A 'applianc':124B 'arbitrari':211C,291C 'attack':147B,195C,250C,281C,288C 'attribut':231C 'authent':193C 'bound':135B 'caus':218C,302C 'cisco':5A,14A,18A,27A,32A,34A,36A,38A,40A,42A,44A,46A,48A,50A,52A,54A,56A,58A,60A,62A,64A,66A,68A,70A,72A,74A,76A,78A,80A,82A,84A,86A,88A,90A,92A,94A,96A,98A,100A,102A,104A,106A,108A,110A,112B,125B,173C,182C,186C 'code':163B,212C,292C 'compromis':257C 'condit':315C 'configur':265C 'control':150B,199C,278C,296C 'could':190C,251C,285C 'crash':168B,222C 'cve':21A,24A 'denial':311C 'detail':321C,322C 'devic':166B,216C,220C 'domain':235C 'dos':314C 'due':226C 'either':201C,256C 'encrypt':7A,140B,175C 'execut':210C,290C 'exploit':113B,252C,284C 'featur':12A,145B,180C,248C 'full':295C 'g':241C 'g-ikev2':240C 'gain':294C 'gdoi':238C 'get':10A,115B,143B,153B,178C,246C 'get-vpn':114B 'group':6A,139B,155B,174C,203C,234C,268C 'ikev2':242C 'inform':318C 'infrastructur':117B 'instal':259C 'insuffici':228C 'interpret':237C 'io':15A,19A,118B,120B,126B,128B,183C,187C 'ios':28A,30A,33A,35A,37A,39A,41A,43A,45A,47A,49A,51A,53A,55A,57A,59A,61A,63A,65A,67A,69A,71A,73A,75A,77A,79A,81A,83A,85A,87A,89A,91A,93A,95A,97A,99A,101A,103A,105A,107A,109A,111A 'ios-x':119B 'key':158B,207C,260C,274C 'malici':162B 'member':156B,204C,269C 'modifi':263C 'network':123B 'network-appli':122B 'out-of-bound':132B 'point':271C 'protocol':243C 'reload':307C 'remot':194C 'result':308C 'run':161B 'section':323C 'see':319C 'server':159B,208C,261C,275C 'servic':313C 'softwar':16A,184C,189C 'success':283C 'system':300C,305C 'transport':8A,141B,176C 'valid':229C 'vpn':9A,11A,116B,142B,144B,154B,177C,179C,247C 'vulner':2A,170C,224C,254C 'write':136B 'xe':20A,31A,121B,129B,188C","nicknames":[],"mitigations":[],"who_affected":null,"tier":null,"verified":{},"analyst_revisit_at":null,"first_public_at":"2023-09-27T18:15:10+00:00","kev":{"dateAdded":"2023-10-10","dueDate":"2023-10-31","requiredAction":"Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.","knownRansomwareCampaignUse":"Unknown"},"cvss_vector":"CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H","cvss_by":"psirt@cisco.com","poc_count":0,"sources":[{"source":"kev","external_id":"CVE-2023-20109","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2023-20109","severity":null,"published_at":"2023-10-10T00:00:00+00:00","modified_at":null,"first_seen_at":"2026-10-23T19:11:51+00:00","fetched_at":"2026-10-25T10:39:05+00:00","note":null},{"source":"nvd","external_id":"CVE-2023-20109","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-20109","severity":null,"published_at":"2023-09-27T18:15:10+00:00","modified_at":"2026-06-17T05:29:29+00:00","first_seen_at":"2026-10-23T22:29:04+00:00","fetched_at":"2026-10-23T22:29:04+00:00","note":null}],"documents":[],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}