Asterisk: ARI setChannelVar bypasses live_dangerously and permits FILE() writes
- 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- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean?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
- Exploitation: none
- Automatable: no
- Technical impact: total
Summary
Asterisk, an open source telephony toolkit (private branch exchange), is affected through its REST Interface (ARI). An attacker holding read-only ARI credentials can bypass the "live_dangerously" safety setting and write files to the server's filesystem via dialplan functions.
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 authenticated Asterisk REST Interface (ARI) attacker with read-only privileges may use `setChannelVar` to execute write dialplan functions, including `FILE()` writes, even when `live_dangerously` in `asterisk.conf` is set to no. The Asterisk HTTP web server must be enabled and reachable, and the attacker must already have valid `read-only ARI credentials`. HTTP is disabled by default and 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.
Timeline
- CVE published
- First seen by cve.now
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: total
- Record last updated
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