An issue was discovered in PJSIP in Asterisk before 16.19.1 and before 18.5.1.
Priority LOW 34CWE-617Published · 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
- No fix listed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-617.
Summary
An issue was discovered in PJSIP in Asterisk before 16.19.1 and before 18.5.1. To exploit, a re-INVITE without SDP must be received after Asterisk has sent a BYE request.
Why it matters now
EPSS 0.02463 84th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix No fix listed No fixed version in the sources yet
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 6
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:digium:asterisk:16.17.0:*:*:*:*:*:*:* | 16.17.0 | Vulnerable | Digium |
| cpe:2.3:a:digium:asterisk:16.18.0:*:*:*:*:*:*:* | 16.18.0 | Vulnerable | Digium |
| cpe:2.3:a:digium:asterisk:16.19.0:*:*:*:*:*:*:* | 16.19.0 | Vulnerable | Digium |
| cpe:2.3:a:digium:asterisk:18.3.0:*:*:*:*:*:*:* | 18.3.0 | Vulnerable | Digium |
| cpe:2.3:a:digium:asterisk:18.4.0:*:*:*:*:*:*:* | 18.4.0 | Vulnerable | Digium |
| cpe:2.3:a:digium:asterisk:18.5.0:*:*:*:*:*:*:* | 18.5.0 | Vulnerable | Digium |
- cpe:2.3:a:digium:asterisk:16.17.0:*:*:*:*:*:*:* Versions 16.17.0 Vulnerable ·Digium
- cpe:2.3:a:digium:asterisk:16.18.0:*:*:*:*:*:*:* Versions 16.18.0 Vulnerable ·Digium
- cpe:2.3:a:digium:asterisk:16.19.0:*:*:*:*:*:*:* Versions 16.19.0 Vulnerable ·Digium
- cpe:2.3:a:digium:asterisk:18.3.0:*:*:*:*:*:*:* Versions 18.3.0 Vulnerable ·Digium
- cpe:2.3:a:digium:asterisk:18.4.0:*:*:*:*:*:*:* Versions 18.4.0 Vulnerable ·Digium
- cpe:2.3:a:digium:asterisk:18.5.0:*:*:*:*:*:*:* Versions 18.5.0 Vulnerable ·Digium
Remediation
No fixed version listed by the sources yet.
Vendor assessments
Timeline
- 2026-10-02 Threatist record created from CVE-2021-31878
- 2026-10-03 Alias added: GHSA-h6p9-w9r4-7x73
References
More Digium Asterisk vulnerabilities
- TI-2006-05256 Integer overflow in the get_input function in the Skinny channel driver (chan_skinny.c)… CVSS 2.0HIGH 7.5
- TI-2017-12542 An issue was discovered in chan_skinny.c in Asterisk Open Source 13.18.2 and older… CVSS 3.0HIGH 7.5
- TI-2023-27195 Asterisk susceptible to Denial of Service via DTLS Hello packets during call initiation CVSS 3.1HIGH 7.5
- TI-2017-13083 An issue was discovered in Asterisk 13.18.4 and older, 14.7.4 and older, 15.1.4 and… CVSS 3.0HIGH 7.5
- TI-2019-13459 An issue was discovered in manager.c in Sangoma Asterisk through 13.x, 16.x, 17.x and… CVSS 3.1HIGH 8.8
- TI-2018-05283 A Buffer Overflow issue was discovered in Asterisk through 13.19.1, 14.x through 14.7.5… CVSS 3.0HIGH 7.5
Sources
- CVE-2021-31878 · CVE Program
- CVE-2021-31878 · NVD
- FIRST EPSS
- GHSA-h6p9-w9r4-7x73 · GitHub Advisory Database · CC BY 4.0
- CVE-2021-31878 · 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