Asterisk ast_loggrabber runs scripts from world-writable /tmp
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- Passive
- Attack complexity
- Low
- Attack requirements
- Present
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · None
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-426.
Summary
ast_loggrabber in Asterisk runs a Python script from the world-writable /tmp directory (CWE-426). An attacker already authorized to open a shell can plant a malicious script there and gain elevated privileges when an administrator runs the tool with elevated rights. Affected are Asterisk before 20.20.1, from 21.0.0-pre1 before 21.12.3, from 22.0.0-pre1 before 22.10.1, from 23.0.0-pre1 before 23.4.1, Certified Asterisk before 20.7-cert11 and from 22.8-cert1-pre1 before 22.8-cert3.
Written with Claude Haiku 5.5 from the sources below · 2026-11-02
Description from the CNA
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, `ast_loggrabber` executes a `Python script` from the world-writable `/tmp` directory. An attacker already authorized to open a shell session on the Asterisk server may place a malicious script there and gain elevated privileges or execute code when an administrator runs `ast_loggrabber` as a user with elevated privileges. 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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| asterisk | asterisk | before 20.20.1; 21.0.0-pre1 to before 21.12.3; 22.0.0-pre1 to before 22.10.1; 23.0.0-pre1 to before 23.4.1 | 20.20.1, 21.12.3, 22.10.1, 23.4.1 | Patch available | CNA |
| asterisk | certified-asterisk | before 20.7-cert11; 22.8-cert1-pre1 to before 22.8-cert3 | 20.7-cert11, 22.8-cert3 | Patch available | CNA |
- asterisk Vendorasterisk Affected before 20.20.1; 21.0.0-pre1 to before 21.12.3; 22.0.0-pre1 to before 22.10.1; 23.0.0-pre1 to before 23.4.1 Fixed in 20.20.1, 21.12.3, 22.10.1, 23.4.1 Patch available CNA
- certified-asterisk Vendorasterisk Affected before 20.7-cert11; 22.8-cert1-pre1 to before 22.8-cert3 Fixed in 20.7-cert11, 22.8-cert3 Patch available CNA
Remediation
Upgrade Asterisk to 20.20.1, 21.12.3, 22.10.1 or 23.4.1, and Certified Asterisk to 20.7-cert11 or 22.8-cert3.
Written with Claude Haiku 5.5 from the sources below · 2026-11-02
- Fix · CNA asterisk (asterisk) Fixed in 20.20.1, 21.12.3, 22.10.1, 23.4.1
- Fix · CNA certified-asterisk (asterisk) Fixed in 20.7-cert11, 22.8-cert3
Vendor assessments
Timeline
- 2026-10-27 Threatist record created from CVE-2026-57203
- 2026-10-28 Priority changed: MEDIUM → LOW
- 2026-10-29 CISA SSVC decision points changed
- 2026-11-02 Affected versions changed · Red Hat
- 2026-11-02 CVSS score added · Red Hat
References
Other 14
- https://github.com/asterisk/asterisk/security/advisories/GHSA-xgj6-2gc5-5x9c
- https://github.com/asterisk/asterisk/commit/022407ec47adebe27b7ec8bcf5626e5a02fe1551
- https://github.com/asterisk/asterisk/commit/a51c4e3d6bccce4bc4226c43e78952573a62f165
- https://github.com/asterisk/asterisk/commit/ba8e5bdecd5280fc0ab230df59e41ea21b3a052f
- https://github.com/asterisk/asterisk/commit/bd63fe121d0e86867863bd98b5771e592273b035
- https://github.com/asterisk/asterisk/commit/c0fc2ae54cb6289a48a80333432f5fdf5a40c7de
- https://github.com/asterisk/asterisk/commit/f18ac4c964781f671e400342790bf40679698067
- https://github.com/asterisk/asterisk/releases/tag/20.20.1
- https://github.com/asterisk/asterisk/releases/tag/21.12.3
- https://github.com/asterisk/asterisk/releases/tag/22.10.1
- https://github.com/asterisk/asterisk/releases/tag/23.4.1
- https://github.com/asterisk/asterisk/releases/tag/certified-20.7-cert11
- https://github.com/asterisk/asterisk/releases/tag/certified-22.8-cert3
- https://github.com/asterisk/asterisk/tree/24.0.0-pre1
More asterisk vulnerabilities
- TI-2025-30244 Using malformed From header can forge identity with ";" or NULL in name portion CVSS 3.1HIGH 7.7
- TI-2023-27195 Asterisk susceptible to Denial of Service via DTLS Hello packets during call initiation CVSS 3.1HIGH 7.5
- TI-2024-28351 Asterisk allows `Write=originate` as sufficient permissions for code execution / `System()` dialplan CVSS 3.1HIGH 8.8
- TI-2025-00959 Asterisk Unsafe Shell Sourcing in safe_asterisk Leads to Local Privilege Escalation CVSS 4.0HIGH 7.0
- TI-2025-34699 Asterisk remotely exploitable leak of RTP UDP ports and internal resources CVSS 3.1MEDIUM 6.5
- TI-2025-31747 Asterisk is Vulnerable to Remote DoS and possible RCE Attacks During Memory Allocation CVSS 3.1MEDIUM 6.5
Sources
- CVE-2026-57203 · CVE Program
- CVE-2026-57203 · NVD
- FIRST EPSS
- CVE-2026-57203 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences