Asterisk: chan_unistim DIALPAGE digit handling can overflow phone_number and crash Asterisk
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 20.20.1, 21.12.3, 22.10.1, 23.4.1, 20.7-cert11, and 1 more
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
Asterisk, an open source telephony toolkit, is affected through its chan_unistim module, which handles Unistim phone connections. An attacker who can reach the module's UDP port and send a specially crafted packet can trigger a memory overflow that crashes the Asterisk service.
Summarized by anthropic/claude-haiku-5.5. Verify details against the original sources.
Read the original 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, an out-of-bounds write in `chan_unistim` `DIALPAGE` digit handling can overflow the `phone_number` field and crash Asterisk when an attacker sends a carefully crafted incoming request packet. The `chan_unistim` module must be loaded and configured with a valid `UNISTIM UDP port` that the attacker can reach. The attacker must register as a configured `phone MAC`, or the deployment must have an equivalent `production/autoprovisioning` path that allows the client to reach the main page. 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.
Timeline
- CVE published
- First seen by cve.now
Affected versions
- asterisk asterisk
fixed in 20.20.1; From 21.0.0-pre1 · fixed in 21.12.3; From 22.0.0-pre1 · fixed in 22.10.1; From 23.0.0-pre1 · fixed in 23.4.1
- asterisk certified-asterisk
fixed in 20.7-cert11; From 22.8-cert1-pre1 · fixed in 22.8-cert3