{"id":"CVE-2026-57195","kind":"vulnerability","aliases":["CVE-2026-57195"],"related":[],"title":"Asterisk: NULL pointer dereference in AMI over HTTP crashes the server","description":"Asterisk is an open source private branch exchange and telephony toolkit. Prior to Asterisk 20.20.1, 21.12.3, 22.10.1, 23.4.1 and Certified Asterisk 20.7-cert11, 22.8-cert3, a NULL pointer dereference in the `Asterisk Manager Interface (AMI)` may allow an unauthenticated attacker to crash Asterisk when `Digest Authentication` is used via `HTTP`. The Asterisk `HTTP` web server, AMI, and AMI access via `HTTP` must all be enabled; each is disabled by default. The attacker must be able to connect to the `HTTP` server, which binds only to `127.0.0.1` by default even when enabled. This issue is fixed in Asterisk 20.20.1, 21.12.3, 22.10.1, 23.4.1 and Certified Asterisk 20.7-cert11, 22.8-cert3.","summary":"A NULL pointer dereference in the Asterisk Manager Interface, reached over HTTP with Digest Authentication, lets an unauthenticated attacker crash Asterisk. The sources describe a denial of service, not code execution.","severity":"high","cvss":7.5,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["asterisk","package","self-hosted","telephony","voip"],"not_affected_if":["ami-http-disabled","default-config","http-disabled"],"how_to_check":"- Run `asterisk -rx \"core show version\"` to read the installed version.\n- Check `http.conf` for `enabled=yes` and `manager.conf` for `enabled=yes` and `webenabled=yes`; all three must be on for exposure.\n- Check the HTTP bind address in `http.conf`; the default is `127.0.0.1`.","fix":"- Upgrade Asterisk to `20.20.1`, `21.12.3`, `22.10.1` or `23.4.1`, or Certified Asterisk to `20.7-cert11` or `22.8-cert3`.\n- If an upgrade is not possible, disable AMI over HTTP (`webenabled=no` in `manager.conf`) or disable the HTTP server.","status":"open","published_at":"2026-10-27T21:18:06+00:00","first_seen_at":"2026-10-27T21:29:22+00:00","triaged_at":"2026-10-27T21:30:20+00:00","updated_at":"2026-10-27T21:30:20+00:00","category":"package","confidence":0.8,"triage":{"at":"2026-10-27T21:30:20Z","model":"claude-haiku-5-5","output":{"fix":"- Upgrade Asterisk to `20.20.1`, `21.12.3`, `22.10.1` or `23.4.1`, or Certified Asterisk to `20.7-cert11` or `22.8-cert3`.\n- If an upgrade is not possible, disable AMI over HTTP (`webenabled=no` in `manager.conf`) or disable the HTTP server.","reach":"network","title":"Asterisk: NULL pointer dereference in AMI over HTTP crashes the server","impact":"medium","summary":"A NULL pointer dereference in the Asterisk Manager Interface, reached over HTTP with Digest Authentication, lets an unauthenticated attacker crash Asterisk. The sources describe a denial of service, not code execution.","category":"package","nicknames":[],"who_cares":["asterisk","telephony","self-hosted","voip"],"confidence":0.8,"needs_auth":"no","worst_case":"Asterisk crashes, taking down phone service until it restarts.","analyst_note":"","how_to_check":"- Run `asterisk -rx \"core show version\"` to read the installed version.\n- Check `http.conf` for `enabled=yes` and `manager.conf` for `enabled=yes` and `webenabled=yes`; all three must be on for exposure.\n- Check the HTTP bind address in `http.conf`; the default is `127.0.0.1`.","needs_analyst":false,"not_affected_if":["default-config","http-disabled","ami-http-disabled"],"who_is_affected":"Only systems running Asterisk with the HTTP server, AMI and AMI-over-HTTP all enabled, with Digest Authentication in use, are exposed. The HTTP server binds to localhost by default, so exposure needs a deliberately reachable bind address. Systems that keep the defaults can skip the emergency patch but should still upgrade.","user_interaction":"no","needs_special_setup":"yes","severity_if_unknown":"high"},"cost_usd":0.000689,"input_tokens":3517,"output_tokens":675,"severity_before":"high"},"analyst_status":null,"analyst_note":null,"search":"'-2026':13A,16A '-57195':14A,17A '127.0.0.1':141C '20.20.1':70C,153C '20.7':77C,160C '21.12.3':71C,154C '22.10.1':72C,155C '22.8':79C,162C '23.4.1':73C,156C 'abl':130C 'access':114C 'allow':92C 'ami':6A,90C,111C,113C 'asterisk':1A,18B,31B,45B,56C,69C,76C,87C,98C,107C,152C,159C 'attack':43B,95C,127C 'authent':39B,101C 'bind':138C 'branch':62C 'cert11':78C,161C 'cert3':80C,163C 'certifi':75C,158C 'code':54B 'connect':132C 'crash':9A,44B,97C 'cve':12A,15A 'default':125C,143C 'denial':50B 'derefer':4A,28B,84C 'describ':48B 'digest':38B,100C 'disabl':123C 'enabl':120C,146C 'even':144C 'exchang':63C 'execut':55B 'fix':150C 'host':22B 'http':8A,36B,105C,108C,116C,135C 'interfac':33B,89C 'issu':148C 'let':40B 'manag':32B,88C 'may':91C 'must':117C,128C 'null':2A,26B,82C 'open':59C 'packag':19B 'pointer':3A,27B,83C 'prior':67C 'privat':61C 'reach':34B 'self':21B 'self-host':20B 'server':11A,110C,136C 'servic':52B 'sourc':47B,60C 'telephoni':23B,65C 'toolkit':66C 'unauthent':42B,94C 'use':103C 'via':104C,115C 'voip':24B 'web':109C","nicknames":[],"mitigations":[],"who_affected":"Only systems running Asterisk with the HTTP server, AMI and AMI-over-HTTP all enabled, with Digest Authentication in use, are exposed. The HTTP server binds to localhost by default, so exposure needs a deliberately reachable bind address. Systems that keep the defaults can skip the emergency patch but should still upgrade.","tier":"B","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-27T21:18:06+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cvss_by":"security-advisories@github.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-57195","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-57195","severity":null,"published_at":"2026-10-27T21:18:06+00:00","modified_at":"2026-10-27T21:18:06+00:00","first_seen_at":"2026-10-27T21:29:22+00:00","fetched_at":"2026-10-27T21:29:22+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"}