What is CVE-2026-104811?

CVE-2026-104811 is Mitel MiVoice Office 400 Music on Hold WAV File Upload Code Execution. The supplied enrichment data classifies it as File Upload mapped to CWE-434 Unrestricted Upload of File with Dangerous Type; CWE-20 Improper Input Validation; CWE-94 Code Injection; CWE-829 CWE-829.

Which versions are affected?

Affected product and version evidence is listed in the product table above. Current public advisories should be checked for exact version scope before patch targeting is finalized.

Is there active exploitation?

Active exploitation is not confirmed from current sources for CVE-2026-104811. If exploitation is not confirmed from current sources, teams should document that status and continue monitoring KEV, vendor, and telemetry updates.

No. CVE-2026-104811 is not listed in CISA KEV in the supplied enrichment data. KEV status should be monitored because it can change after initial disclosure or after exploitation becomes publicly confirmed.

Is there a public exploit?

1 public PoC repositories reported; 0 marked weaponized in current dataset. Public exploit or PoC availability should raise triage priority, especially for exposed or business-critical systems.

How can defenders detect it?

Start with Not reported where available. Look for vulnerability-class behavior, product errors, suspicious authentication events, exploit probes, and abnormal process activity based only on evidence that applies to the affected product.

How should teams prioritize it?

Prioritize CVE-2026-104811 using CVSS 8.4, EPSS 0%, KEV status, public PoC status, and asset exposure. Internet-facing, privileged, or business-critical deployments should be handled first.

Are workarounds available?

The supplied mitigation guidance says to apply vendor patches and restrict external exposure until fixed. Fixed-version evidence is listed in the mitigation section above.

Which threat actors are linked publicly?

No public threat actor linkage is confirmed from current sources. Do not attribute exploitation to a threat actor unless the source evidence explicitly supports that linkage.

What should be done in the next 24 hours?

Identify exposed assets running affected vendor/product/version combinations. Prioritize based on EPSS, PoC availability, and external exposure. Search available logs for exploit probes, errors, authentication anomalies, or suspicious child processes matching the vulnerability class. Open remediation tickets with affected assets, owners, evidence status, and detection coverage so decisions are traceable.

highFile Uploadpublic exploit

CVE-2026-104811

CVE-2026-104811 — Mitel MiVoice Office 400 Music on Hold WAV File Upload Code Execution

DigitalCanion SA has discovered a vulnerability that allows remote attackers to execute arbitrary code on affected installations of the product. Authentication may be required to exploit this vulnerability. The specific flaw exists within the Configuration → Services → Music on Hold functionality of the web portal listening on TCP port 443. The application is intended to allow users to upload WAV audio files but fails to properly validate the uploaded file type. An attacker can exploit this behavior to upload a malicious shared object (.so) instead of a WAV file. When the uploaded file is subsequently processed by the affected component, attacker-controlled code is loaded and executed in the context of the affected process. This can result in remote code execution and potentially full compromise of the underlying Linux system.

Published Oct 5, 2026Updated Oct 5, 2026Sources: NVD, Mitel (CNA), GitHub, GitHub Security Advisory, SOCRadar CTI

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.

Exploitation

Exploit code

public exploit, none observed

EPSS

ahead of 0% of scored CVEs

Affects

Mitel

Mitel MiVoice Office 400

CVSS base

8.4

high

Remediation

The vendor's own words where we have them.

Upgrade Mitel MiVoice Office 400 to a fixed release. Apply vendor patches per advisory and restrict external exposure of the affected component until patched.

First 24 hours

Ordered from the record's own fields — exposure first, because you cannot patch what you have not found.

Identify exposed assets running affected vendor/product/version combinations.
Prioritize based on EPSS, PoC availability, and external exposure.
Search available logs for exploit probes, errors, authentication anomalies, or suspicious child processes matching the vulnerability class.

Affected scope

Vendor, product and version as the advisories word them.

Vendor	Product	Versions	Status
Mitel	Mitel MiVoice Office 400	11.0.96.0	Vulnerable

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Scope

Attack Complexity

Low

Attack Vector

Local

Privileges Req

High

User Interaction

None

Every base score collected

Sources score independently and disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Source
8.4	CVSS 4.0	high	—	—	Mitel (CNA)

CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:P/AU:Y/U:Amber

What this weakness leads to

MITRE's own consequences and mitigations for the weakness class — the authority's wording, not guidance derived from the CVSS vector.

MITRE

CWE-434 · Unrestricted Upload of File with Dangerous Type

Execute Unauthorized Code or Commands

Mitigation: Generate a new, unique filename for an uploaded file instead of using the user-supplied filename, so that no external input is used at all.[REF-422] [REF-423]

CWE-829 · Inclusion of Functionality from Untrusted Control Sphere

Execute Unauthorized Code or Commands

Mitigation: Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.

Weakness & attack patterns

CWE-434Unrestricted Upload of File with Dangerous Type
CWE-20Improper Input Validation
CWE-94Code Injection
CWE-829

Attack patterns reported against this CVE. The ATT&CK techniques below are inferred from its weakness class.

CAPEC-67 · String Format Overflow in syslog()CAPEC-261 · Fuzzing for garnering other adjacent user/sensitive dataCAPEC-182 · Flash InjectionCAPEC-267 · Leverage Alternate EncodingCAPEC-71 · Using Unicode Encoding to Bypass Validation LogicCAPEC-46 · Overflow Variables and TagsCAPEC-83 · XPath InjectionCAPEC-22 · Exploiting Trust in ClientCAPEC-3 · Using Leading 'Ghost' Character Sequences to Bypass Input FiltersCAPEC-13 · Subverting Environment Variable ValuesCAPEC-8 · Buffer Overflow in an API CallCAPEC-250 · XML Injection

T1574.010Hijack Execution Flow: ServicesFile Permissions Weakness
T1562.003Impair Defenses: Impair Command History Logging
T1574.006Hijack Execution Flow: Dynamic Linker Hijacking

Public exploit

Capability, not use: code existing is a different claim from anyone running it.

Repositories

Detection

Read off the CVSS vector and the weakness class. Starting points, not rules we have tested.

Monitor for scanner or exploit-pattern traffic after 1 public PoC repositories were reported.

Timeline

What happened to this CVE, newest first — with the readings a source repeats on a schedule counted underneath rather than listed.

2026
Added · CVSS 3.1 8.4 (AV:L)
Oct 5, 2026 · NVD
Initial · CVE published
Oct 5, 2026 · NVD
Added · GHSA-g7mp-v763-325c published (high)
Oct 5, 2026 · GitHub Security Advisory
CVE published by MITRE.
Oct 5, 2026 · SOCRadar CTI

Source activity

Readings a source repeats on a schedule, counted rather than listed.

1×CVE modified by NIST: CWE updated.Oct 5, 2026 · SOCRadar CTI

References

3 on the record

digitalcanion.com/en/security-research/#vendor=mitel&status=cna
Vendor Advisory
nvd.nist.gov/vuln/detail/CVE-2026-104811
NVD
github.com/advisories/GHSA-g7mp-v763-325c
Exploit, Third Party Advisory

Elsewhere on this site

Mitelevery CVE for this vendor
File Uploadsame class
CWE-434other pages naming this weakness

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record1

What should defenders know first?

CVE-2026-104811 is Mitel MiVoice Office 400 Music on Hold WAV File Upload Code Execution, a high vulnerability affecting Mitel MiVoice Office 400 from Mitel. The current evidence does not list it in CISA KEV, and the exploit status is: Active exploitation is not confirmed from current sources for CVE-2026-104811. Public exploit evidence is: 1 public PoC repositories reported; 0 marked weaponized in current dataset. The affected-version evidence is listed in the key facts and affected products tables. Defenders should first verify whether exposed or business-critical assets run those versions, then apply vendor patches or mitigations, restrict reachable attack surface, and preserve logs for detection review. CVSS 8.4 describes technical severity, while EPSS 0% helps estimate near-term exploit likelihood; neither replaces asset context. Unknown fields should remain explicit in tickets, and threat actor, IOC, victimology, or payload claims should not be added unless a cited source supports them. Monitor CISA KEV, vendor advisories, NVD changes, public PoC repositories, and internal telemetry for update triggers.