CVE-2026-106803

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.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://gist.github.com/hackeryounow/7d7ccc9ec501a5d8c9143b2e1bcc11cb
https://github.com/kamailio/kamailio/commit/21261436492f0014930e804e20586e3833bb91b9
https://github.com/kamailio/kamailio/issues/4954
https://github.com/kamailio/kamailio/pull/4958
https://github.com/kamailio/kamailio/issues/4954

Configurations

No configuration.

History

03 Nov 2026, 14:17

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 9.8
CWE		CWE-121
References	~~() https://github.com/kamailio/kamailio/issues/4954 -~~	() https://github.com/kamailio/kamailio/issues/4954 -

02 Nov 2026, 17:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-11-02 17:17

Updated : 2026-11-03 14:17

NVD link : CVE-2026-106803

Mitre link : CVE-2026-106803

CVE.ORG link : CVE-2026-106803

JSON object : View

Products Affected

No product.

CWE

CWE-121

Stack-based Buffer Overflow

{"id": "CVE-2026-106803", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-106803", "role": "CISA Coordinator", "options": [{"exploitation": "poc"}, {"automatable": "yes"}, {"technicalImpact": "total"}], "version": "2.0.3", "timestamp": "2026-11-03T13:31:38.995410Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 9.8, "attackVector": "NETWORK", "baseSeverity": "CRITICAL", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 3.9}]}, "affected": [{"source": "cve@mitre.org", "affectedData": [{"vendor": "n/a", "product": "n/a", "versions": [{"status": "affected", "version": "n/a"}]}]}], "published": "2026-11-02T17:17:33.270", "references": [{"url": "https://gist.github.com/hackeryounow/7d7ccc9ec501a5d8c9143b2e1bcc11cb", "source": "cve@mitre.org"}, {"url": "https://github.com/kamailio/kamailio/commit/21261436492f0014930e804e20586e3833bb91b9", "source": "cve@mitre.org"}, {"url": "https://github.com/kamailio/kamailio/issues/4954", "source": "cve@mitre.org"}, {"url": "https://github.com/kamailio/kamailio/pull/4958", "source": "cve@mitre.org"}, {"url": "https://github.com/kamailio/kamailio/issues/4954", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}], "vulnStatus": "Awaiting Analysis", "weaknesses": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "description": [{"lang": "en", "value": "CWE-121"}]}], "descriptions": [{"lang": "en", "value": "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."}], "lastModified": "2026-11-03T14:17:17.387", "sourceIdentifier": "cve@mitre.org"}