Asterisk is Vulnerable to Remote DoS and possible RCE Attacks During Memory Allocation
Priority MEDIUM 62CWE-476Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-476.
Summary
Asterisk is an open source private branch exchange and telephony toolkit. In versions up to and including 18.26.2, between 20.00.0 and 20.15.0, 20.7-cert6, 21.00.0, 22.00.0 through 22.5.0, there is a remote DoS and possible RCE condition in `asterisk/res/res_stir_shaken /verification.c` that can be exploited when an attacker can set an arbitrary Identity header, or STIR/SHAKEN is enabled, with verification set in the SIP profile associated with the endpoint to be attacked. This is fixed in versions 18.26.3, 20.7-cert6, 20.15.1, 21.10.1 and 22.5.1.
Why it matters now
Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.0053 45th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed asterisk (asterisk): 18.26.3, 20.15.1, 21.10.1 +2
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- No
- Technical impact
- Partial
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 18.26.3; 20.00.0 to before 20.15.1; 21.00.0 to before 21.10.1; 22.00.0 to before 22.5.1; 20.7-cert6 to before 20.7-cert7 | 18.26.3, 20.15.1, 21.10.1, 22.5.1, 20.7-cert7 | Patch available | CNA |
- asterisk Vendorasterisk Affected before 18.26.3; 20.00.0 to before 20.15.1; 21.00.0 to before 21.10.1; 22.00.0 to before 22.5.1; 20.7-cert6 to before 20.7-cert7 Fixed in 18.26.3, 20.15.1, 21.10.1, 22.5.1, 20.7-cert7 Patch available CNA
CPE configurations NVD · 10
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:sangoma:asterisk:*:*:*:*:*:*:*:* | before 18.26.3; 20.0.0 to before 20.15.1; 21.0.0 to before 21.10.1; 22.0.0 to before 22.5.1 | Vulnerable | Sangoma |
| cpe:2.3:a:sangoma:certified_asterisk:*:*:*:*:*:*:*:* | up to 18.9 | Vulnerable | Sangoma |
| cpe:2.3:a:sangoma:certified_asterisk:20.7:cert1:*:*:*:*:*:* | 20.7 cert1 | Vulnerable | Sangoma |
| cpe:2.3:a:sangoma:certified_asterisk:20.7:cert1-rc1:*:*:*:*:*:* | 20.7 cert1-rc1 | Vulnerable | Sangoma |
| cpe:2.3:a:sangoma:certified_asterisk:20.7:cert1-rc2:*:*:*:*:*:* | 20.7 cert1-rc2 | Vulnerable | Sangoma |
| cpe:2.3:a:sangoma:certified_asterisk:20.7:cert2:*:*:*:*:*:* | 20.7 cert2 | Vulnerable | Sangoma |
| cpe:2.3:a:sangoma:certified_asterisk:20.7:cert3:*:*:*:*:*:* | 20.7 cert3 | Vulnerable | Sangoma |
| cpe:2.3:a:sangoma:certified_asterisk:20.7:cert4:*:*:*:*:*:* | 20.7 cert4 | Vulnerable | Sangoma |
| cpe:2.3:a:sangoma:certified_asterisk:20.7:cert5:*:*:*:*:*:* | 20.7 cert5 | Vulnerable | Sangoma |
| cpe:2.3:a:sangoma:certified_asterisk:20.7:cert6:*:*:*:*:*:* | 20.7 cert6 | Vulnerable | Sangoma |
- cpe:2.3:a:sangoma:asterisk:*:*:*:*:*:*:*:* Versions before 18.26.3; 20.0.0 to before 20.15.1; 21.0.0 to before 21.10.1; 22.0.0 to before 22.5.1 Vulnerable ·Sangoma
- cpe:2.3:a:sangoma:certified_asterisk:*:*:*:*:*:*:*:* Versions up to 18.9 Vulnerable ·Sangoma
- cpe:2.3:a:sangoma:certified_asterisk:20.7:cert1:*:*:*:*:*:* Versions 20.7 cert1 Vulnerable ·Sangoma
- cpe:2.3:a:sangoma:certified_asterisk:20.7:cert1-rc1:*:*:*:*:*:* Versions 20.7 cert1-rc1 Vulnerable ·Sangoma
- cpe:2.3:a:sangoma:certified_asterisk:20.7:cert1-rc2:*:*:*:*:*:* Versions 20.7 cert1-rc2 Vulnerable ·Sangoma
- cpe:2.3:a:sangoma:certified_asterisk:20.7:cert2:*:*:*:*:*:* Versions 20.7 cert2 Vulnerable ·Sangoma
- cpe:2.3:a:sangoma:certified_asterisk:20.7:cert3:*:*:*:*:*:* Versions 20.7 cert3 Vulnerable ·Sangoma
- cpe:2.3:a:sangoma:certified_asterisk:20.7:cert4:*:*:*:*:*:* Versions 20.7 cert4 Vulnerable ·Sangoma
- cpe:2.3:a:sangoma:certified_asterisk:20.7:cert5:*:*:*:*:*:* Versions 20.7 cert5 Vulnerable ·Sangoma
- cpe:2.3:a:sangoma:certified_asterisk:20.7:cert6:*:*:*:*:*:* Versions 20.7 cert6 Vulnerable ·Sangoma
Remediation
- Fix · CNA asterisk (asterisk) Fixed in 18.26.3, 20.15.1, 21.10.1, 22.5.1, 20.7-cert7
Vendor assessments
Timeline
- 2026-10-02 Threatist record created from CVE-2025-49832
References
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-2023-26930 Asterisk Path Traversal vulnerability CVSS 3.1HIGH 7.5
Sources
- CVE-2025-49832 · CVE Program
- CVE-2025-49832 · NVD
- FIRST EPSS
- CVE-2025-49832 · 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