CVSS 3.1
9.8 criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HCVE-2026-106803 Stack-based Buffer Overflow
Critical (9.8). EPSS 0.5% estimated probability of exploitation activity in the next 30 days.
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.
Severity
- EPSS
- 0.5% (unchanged from 0.5% a week ago) estimated probability of exploitation activity in the next 30 days; 44th percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- CISA's assessment (SSVC)
- Exploitation: PoC · Automatable: yes · Technical impact: total, assessed 2026-11-03. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
- CWE
- CWE-121 Stack-based Buffer Overflow
- Published
- Modified
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
Ask an AI about this CVE
Show the prompt
Explain CVE-2026-106803 for an engineer deciding whether to act. Use https://cve.bz/api/public/cves/CVE-2026-106803?via=ask-ai-copy and https://cve.bz/cve/CVE-2026-106803?via=ask-ai-copy as the source of truth: what is affected and which versions fix it, whether it is in CISA KEV, public exploits, and its EPSS (an internet-wide 30-day estimate of exploitation activity, not a forecast for my systems). If they give no fixed versions, use the CVE record https://cveawg.mitre.org/api/cve/CVE-2026-106803 or the vendor advisory, not third-party mirrors. Tell me how to check whether I am affected and how to verify a fix. Cite the sources and say where they are uncertain.Opens a third-party assistant; its answer is its own, not cve.bz's. The prompt holds only this CVE's id and public links.
Badge for a README or a site
An image that stays current: it is drawn from the data each time it is fetched (a host that proxies images, as GitHub does, may show its copy for a while). Markdown:
[](https://cve.bz/cve/CVE-2026-106803)
HTML:
<a href="https://cve.bz/cve/CVE-2026-106803"><img src="https://cve.bz/cve/badge/CVE-2026-106803.svg" alt="CVE-2026-106803"></a>
Linux distributions
| Distribution | Release | Package | Fixed in | Advisory |
|---|---|---|---|---|
| Ubuntu | 22.04:LTS, 24.04:LTS, 26.04:LTS and 4 more | kamailio | no fix listed | UBUNTU-CVE-2026-106803 |
From the distributions' data via OSV.dev: Ubuntu Security Notices © Canonical Ltd., CC BY-SA 4.0. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Ubuntu.