External risk intelligence

Openwave Webtop Media Transcoder Allows Unintended Document Conversion

CVE advisoryKnown Exploit

CVE-2026-111793

The product is a media transcoder integrated with webmail systems. While it processes data as part of a web-based service, the specific vulnerability requires an authenticated user to bypass the standard webmail interface to trigger the issue. This suggests it is reachable in internet-facing deployments, but the requirement for authenticated access and a non-standard workflow makes broad public exploitability less certain.

Openwave Webtop Media Transcoder

before 1.1.22.0

Halo Surface Signal: 3 out of 5 — possibly public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

A vulnerability in Openwave Webtop Media Transcoder allows authenticated users to convert unintended document types by bypassing certain restrictions. This could potentially lead to the processing of unauthorized file formats within the webmail experience. The main concern is confirming relevance and exposure to this capability.

Allows conversion of unintended document types.
Matters if authenticated users bypass webmail restrictions.
Confirm relevance and exposure of this capability.

Attack Path

How an attacker could exploit the issue

An authenticated user could bypass the standard Webmail interface to interact directly with the Webtop Media Transcoder. This bypass allows the user to submit unintended document types for conversion, circumventing administrator-set file type restrictions. The system's failure to enforce these restrictions means it will process these unauthorized file types.

Authenticated access required.
Bypass Webmail to submit unintended document types.
Unauthorized file type conversion.

Live Threat

Current exploitation, exposure, and threat context

An authenticated user could bypass file type restrictions in Openwave Webtop Media Transcoder, potentially processing and converting unintended document types. This behavior could occur when an authenticated user bypasses the standard Webmail experience.

Unintended document conversion.
User bypasses Webmail experience.
Service availability may be affected.

Operational Fix

Recommended remediation, mitigation, and detection steps

Application owners and platform teams are likely responsible for addressing this vulnerability in the Openwave Webtop Media Transcoder, as it affects file conversion capabilities within a webmail context. The first practical step involves identifying all instances of the transcoder, assessing their reachability and business criticality, and then confirming the accountable owner before planning remediation.

Identify affected transcoder instances.
Verify owner and assess business criticality.
Plan remediation based on risk.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

Halo Threat Intelligence helps prioritize remediation with Halo Surface Signal and H/A/L/O context. Start exposure validation with a free external attack surface trial.

Free EASM Trial See How Signal Works

Frequently asked questions

What is the Openwave Webtop Media Transcoder?

The Openwave Webtop Media Transcoder is a specialized component used within messaging environments to automatically convert files into different formats. It is typically integrated into webmail systems to ensure that documents sent or received by users are processed into a viewable or compatible state. By managing how media is handled across the platform, it helps maintain consistent file accessibility for end users.

What does CVE-2026-111793 mean?

This vulnerability is classified as CWE-669, or Incorrect Resource Transfer Between Spheres. In plain English, it means the software fails to properly enforce security boundaries that should limit what files the system will process. Because the transcoder does not validate these restrictions, it can be manipulated to accept and convert file types that administrators intended to block.

How can this vulnerability be triggered?

An attacker needs an authenticated account to trigger this issue. The vulnerability occurs when a user intentionally bypasses the standard Webmail interface to interact directly with the transcoder component. Simply using the normal, provided Webmail experience to send or receive files does not trigger the bug; it specifically requires circumventing the established application workflow.

Is my system at risk?

Halo Surface Signal indicates that while this software is often internet-facing as part of webmail services, the risk depends on your specific configuration. Because this flaw requires a user to be authenticated and to actively bypass standard interfaces, it is less accessible to general public traffic than a typical unauthenticated remote attack. You should assess if your architecture allows direct, non-standard interaction with the transcoder.

What should I do to address this issue?

Start by identifying all deployed instances of the Webtop Media Transcoder within your environment. Once identified, verify who owns these assets and assess their overall business criticality. Coordinate with those owners to review system configurations and implement the necessary vendor-provided updates or mitigations to ensure that file type restrictions are properly enforced.

References

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.