Stack-based buffer overflow in Kamailio ims_registrar_pcscf module
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-121 and the CVSS impact.
Summary
Kamailio v6.1.3 and v6.1.4 contain a stack-based buffer overflow (CWE-121) in the ims_registrar_pcscf module. When processing a crafted application/reginfo+xml NOTIFY message, the process_contact() function copies an attacker-controlled port value from the alias parameter into a fixed 5-byte stack buffer without checking its length. An unauthenticated remote attacker can corrupt the stack and terminate the P-CSCF process, causing a denial of service.
Written with Claude Haiku 5.5 from the sources below · 2026-11-03
Description from the CNA
A stack-based buffer overflow exists in Kamailio v6.1.3 and v6.1.4 in the ims_registrar_pcscf module. When processing a crafted application/reginfo+xml NOTIFY message, process_contact() copies an attacker-controlled port value from the alias parameter into a fixed 5-byte stack buffer without validating its length. An unauthenticated remote attacker can trigger stack corruption and terminate the P-CSCF process, resulting in denial of service.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- Yes
- 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 |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
Remediation
The sources list no fixed version for Kamailio.
Written with Claude Haiku 5.5 from the sources below · 2026-11-03
Timeline
- 2026-11-02 Threatist record created from CVE-2026-106803
- 2026-11-02 Alias added: GHSA-g9r9-79hc-j698
- 2026-11-03 CVSS score added · CISA ADP
- 2026-11-03 Weakness changed · CISA ADP
- 2026-11-03 CISA SSVC decision points changed
- 2026-11-03 Priority changed: LOW → HIGH
References
Sources
- CVE-2026-106803 · CVE Program
- CVE-2026-106803 · NVD
- FIRST EPSS
- GHSA-g9r9-79hc-j698 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences