# CVE-2026-106803: CVE-2026-106803

Status: published. Published: 2026-11-02. Updated: 2026-11-03.

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.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- n/a / n/a: Version not specified (affected). Source: CNA: mitre

## Severity and prioritization

- CVSS 3.1: 9.8 (critical); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H; source: ADP: CISA-ADP

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: exploitation poc; automatable yes; technical impact total; source ADP: CISA-ADP

- Weaknesses: CWE-121

## Exploit evidence

- exploit: https://github.com/kamailio/kamailio/issues/4954 (ADP: CISA-ADP)

## References

- https://github.com/kamailio/kamailio/issues/4954 (CNA: mitre)

- https://github.com/kamailio/kamailio/pull/4958 (CNA: mitre)

- https://github.com/kamailio/kamailio/commit/21261436492f0014930e804e20586e3833bb91b9 (CNA: mitre)

- https://gist.github.com/hackeryounow/7d7ccc9ec501a5d8c9143b2e1bcc11cb (CNA: mitre)

- https://github.com/kamailio/kamailio/issues/4954 (ADP: CISA-ADP; exploit)

- https://gist.github.com/hackeryounow/7d7ccc9ec501a5d8c9143b2e1bcc11cb (cve@mitre.org)

- https://github.com/kamailio/kamailio/commit/21261436492f0014930e804e20586e3833bb91b9 (cve@mitre.org)

- https://github.com/kamailio/kamailio/issues/4954 (cve@mitre.org)

- https://github.com/kamailio/kamailio/pull/4958 (cve@mitre.org)

## Provenance

- CNA: mitre: https://www.cve.org/CVERecord?id=CVE-2026-106803; retrieved 2026-11-03; source updated 2026-11-03

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-106803; retrieved 2026-11-03; source updated 2026-11-02

Revision: 104e4dc47637dd9d7c3c3d0550b261938c70efb58a2cf36227d8d8d22ddfebf7

Canonical: https://y2.dev/cve/CVE-2026-106803

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