{"id":"CVE-2026-57199","kind":"vulnerability","aliases":["CVE-2026-57199"],"related":[],"title":"Asterisk: SMS dialplan application overflows buffers, allowing memory corruption or crash","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, `app_sms.c` copies externally controlled `SMS` lengths into `fixed in-struct buffers` without sufficient bounds checks, allowing an attacker to corrupt memory or crash Asterisk. The administrator must explicitly use the `SMS` dialplan application, which is useful when routing calls to or from `analog devices`, and must not have ensured that data passed to the application is valid. 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":"Asterisk's app_sms.c copies externally controlled SMS lengths into fixed in-struct buffers without enough bounds checks. An attacker who can feed data into the SMS dialplan application can corrupt memory or crash Asterisk.","severity":"low","cvss":2.3,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["asterisk","package","self-hosted","telephony"],"not_affected_if":["default-config","sms-application-unused"],"how_to_check":"- Search the dialplan for the `SMS` application (for example with `grep -rn \"SMS(\" /etc/asterisk/`)\n- Confirm the running version with `asterisk -rx \"core show version\"`","fix":"- Upgrade Asterisk to `20.20.1`, `21.12.3`, `22.10.1` or `23.4.1`\n- Upgrade Certified Asterisk to `20.7-cert11` or `22.8-cert3`\n- Until upgraded, remove or stop using the `SMS` dialplan application","status":"open","published_at":"2026-10-27T22:17:27+00:00","first_seen_at":"2026-10-27T22:29:29+00:00","triaged_at":"2026-10-27T22:30:17+00:00","updated_at":"2026-10-27T22:30:17+00:00","category":"package","confidence":0.6,"triage":{"at":"2026-10-27T22:30:17Z","model":"claude-haiku-5-5","output":{"fix":"- Upgrade Asterisk to `20.20.1`, `21.12.3`, `22.10.1` or `23.4.1`\n- Upgrade Certified Asterisk to `20.7-cert11` or `22.8-cert3`\n- Until upgraded, remove or stop using the `SMS` dialplan application","reach":"unknown","title":"Asterisk: SMS dialplan application overflows buffers, allowing memory corruption or crash","impact":"medium","summary":"Asterisk's app_sms.c copies externally controlled SMS lengths into fixed in-struct buffers without enough bounds checks. An attacker who can feed data into the SMS dialplan application can corrupt memory or crash Asterisk.","category":"package","nicknames":[],"who_cares":["asterisk","self-hosted","telephony"],"confidence":0.6,"needs_auth":"unknown","worst_case":"Attacker corrupts Asterisk memory or crashes the telephony server","analyst_note":"","how_to_check":"- Search the dialplan for the `SMS` application (for example with `grep -rn \"SMS(\" /etc/asterisk/`)\n- Confirm the running version with `asterisk -rx \"core show version\"`","needs_analyst":false,"not_affected_if":["sms-application-unused","default-config"],"who_is_affected":"Only systems that explicitly use the SMS dialplan application, typically for routing calls to or from analog devices, are exposed. The administrator must also not have validated the data passed to that application. Systems that do not use the SMS application can skip it.","user_interaction":"unknown","needs_special_setup":"yes","severity_if_unknown":"low"},"cost_usd":0.000637,"input_tokens":3487,"output_tokens":577,"severity_before":"low"},"analyst_status":null,"analyst_note":null,"search":"'-2026':13A,16A '-57199':14A,17A '20.20.1':74C,150C '20.7':81C,157C '21.12.3':75C,151C '22.10.1':76C,152C '22.8':83C,159C '23.4.1':77C,153C 'administr':112C 'allow':7A,102C 'analog':129C 'app':26B,85C 'applic':4A,53B,119C,141C 'asterisk':1A,18B,24B,59B,60C,73C,80C,110C,149C,156C 'attack':44B,104C 'bound':41B,100C 'branch':66C 'buffer':6A,38B,97C 'call':125C 'cert11':82C,158C 'cert3':84C,160C 'certifi':79C,155C 'check':42B,101C 'control':30B,89C 'copi':28B,87C 'corrupt':9A,55B,106C 'crash':11A,58B,109C 'cve':12A,15A 'data':48B,137C 'devic':130C 'dialplan':3A,52B,118C 'enough':40B 'ensur':135C 'exchang':67C 'explicit':114C 'extern':29B,88C 'feed':47B 'fix':34B,93C,147C 'host':22B 'in-struct':35B,94C 'issu':145C 'length':32B,91C 'memori':8A,56B,107C 'must':113C,132C 'open':63C 'overflow':5A 'packag':19B 'pass':138C 'prior':71C 'privat':65C 'rout':124C 'self':21B 'self-host':20B 'sms':2A,31B,51B,90C,117C 'sms.c':27B,86C 'sourc':64C 'struct':37B,96C 'suffici':99C 'telephoni':23B,69C 'toolkit':70C 'use':115C,122C 'valid':143C 'without':39B,98C","nicknames":[],"mitigations":[],"who_affected":"Only systems that explicitly use the SMS dialplan application, typically for routing calls to or from analog devices, are exposed. The administrator must also not have validated the data passed to that application. Systems that do not use the SMS application can skip it.","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-27T22:17:27+00:00","kev":null,"cvss_vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","cvss_by":"security-advisories@github.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-57199","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-57199","severity":null,"published_at":"2026-10-27T22:17:27+00:00","modified_at":"2026-10-27T22:17:27+00:00","first_seen_at":"2026-10-27T22:29:29+00:00","fetched_at":"2026-10-27T22:29:29+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"}