Openwave Messaging (Ireland) Webtop Media Transcoder: Incorrect Resource Transfer Between Spheres (CVE-2026-111793)

What is affected, what to do

Openwave Webtop Media Transcoder does not enforce administrator-defined file type restrictions to restrict the file-types to be converted. This may allow an authenticated user to process and convert unintended document types if bypassing the Webmail experience.

The vulnerability is being actively exploited; treat it as a priority. Update Openwave Messaging (Ireland) Webtop Media Transcoder to version 1.1.22.0. Immediate actions, mitigation and detection rules are in the runbook below.

Affected

• Openwave Messaging (Ireland) Webtop Media Transcoder lt *..1.1.22.0

Fixed in

• Openwave Messaging (Ireland) Webtop Media Transcoder 1.1.22.0

Not sure whether and how you are affected? Ask a question about this vulnerability

Metrics

Response and mitigation

1. 01

   Runbook step 1

   Immediate response (0-24 h)

   • Inventory: Locate every Openwave Webtop Media Transcoder instance (CMDB, package manager, Webtop frontend config) and record the installed version. The context lists 1.1.22.0 as the fixed release. Check the vendor advisory for the exact range of affected earlier versions.
   • Patch: Upgrade to Webtop Media Transcoder 1.1.22.0 or later. Before rollout, confirm in the vendor advisory whether administrator-defined file-type restrictions need to be reloaded or migrated after the update.
   • Cut direct reachability: Until patched, allow transcoder access only from the Webtop webmail frontend. Block direct access from client networks and the internet via firewall or reverse-proxy ACL. Exploitation requires bypassing the webmail experience.
   • Verify configuration: Trim the transcoder's file-type allowlist to what the business actually needs. After patching, test enforcement by sending a disallowed format through a test account and confirming it is rejected.
   • Review suspicious accounts: Identify authenticated users who made anomalous conversion requests in recent weeks. Where abuse is suspected, terminate their sessions and reset their credentials.
2. 02

   Runbook step 2

   Mitigation layers

   • Network segmentation: Place the transcoder in a dedicated backend segment and accept inbound connections only from Webtop frontend servers, with default-deny for everything else. Restrict the transcoder's outbound traffic to the internal services it requires.
   • Reverse proxy/WAF: Add a rule in front of the transcoder endpoint that validates the uploaded file's Content-Type and extension against an allowlist. Block and log any mismatch. This recreates the missing server-side enforcement independently of the product.
   • Conversion engine hardening: Run the transcoder under a dedicated unprivileged service account, and disable macro and script execution in downstream conversion components. Set resource limits (cgroups/ulimit, timeouts, maximum file size) to contain the availability impact of abusive conversions.
   • IAM/least privilege: Expose the conversion feature only to user groups that need it. Make sure service tokens the frontend uses to call the transcoder cannot be harvested by end users.
   • Rate limiting: Cap conversion requests per user per time window at the proxy.
3. 03

   Runbook step 3

   Detection rules

   • Web/proxy logs: Flag transcoder requests whose source IP is not a Webtop frontend server, since these indicate the webmail layer is being bypassed. SPL example: index=proxy dest=<transcoder_host> NOT src_ip IN (<webtop_frontends>) | stats count by src_ip, user, uri
   • File-type mismatch: Search application or proxy logs for conversion requests with extensions or MIME types outside the administrative allowlist. A suitable Sigma shape is selection: uri|contains: <transcoder_path> combined with filter: file_ext not in [allowlist].
   • Process behaviour (EDR/auditd): Alert on unusual child processes or file access by the transcoder service account, such as shells, network utilities, or reads outside its working directory. auditd can capture this with -a always,exit -F arch=b64 -S execve -F uid=<transcoder_uid> -k transcoder_exec
   • Resource telemetry: Correlate CPU, memory, and queue spikes on the transcoder with conversion requests from individual users. Repeated timeouts or crashes tied to a single account suggest abuse.
   • Network (Zeek/Suricata): Detect HTTP sessions to the transcoder with no preceding Webtop session from the same user or source. Matching id.orig_h and referrer in Zeek http.log helps here.

Detection rules

No NEOSEC detection rule is available for this vulnerability yet.

Classification under NIS2 and CRA

Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.

NIS2

NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.

Read in glossary

Actively exploited: treat the vulnerability as a priority in vulnerability handling under Art. 21(2)(e) NIS2. If it is exploited in your environment, check the reporting obligation under Art. 23 (early warning within 24 hours).

CRA

The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.

Read in glossary

Since 11.09.2026, manufacturers of affected products with digital elements must report actively exploited vulnerabilities under Art. 14 CRA, with an early warning within 24 hours via ENISA's single reporting platform.

ISO/IEC 27001

ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.

Read in glossary

Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.

Description

Openwave Webtop Media Transcoder does not enforce administrator-defined file type restrictions to restrict the file-types to be converted. This may allow an authenticated user to process and convert unintended document types if bypassing the Webmail experience.

Source: cvelistv5, NVD (NIST), CISA KEV Catalog, ENISA EUVD

Weakness classes (CWE)

• CWE-669Incorrect Resource Transfer Between Spheres

  Class

  The product does not properly transfer a resource/behavior to another sphere, or improperly imports a resource/behavior from another sphere, in a manner that provides unintended control over that resource.

  Entry at MITRE CWE-669

References & sources

• openwave.aieuvd, Product
• github.comGISOpenwave/security-advisories-public/blob/main/CAN-2026-20326…euvd, Third-party advisory
• jvn.jpen/vu/JVNVU93403064Third-party advisory, Third-party advisory
• cisa.govknown-exploited-vulnerabilities-catalog?field_cve=CVE-2026-1117…US government resource, government-resource

Changes to this CVE

Who changed this CVE and when: NVD (analysis, affected products, CVSS), the CVE publisher (CNA) and additional providers such as CISA (ADP).

1. 11.11.2026Record modifiedCISA ADP

   CISA assessment (SSVC): exploitation: active, automatable: no

   Show 2 original changes

   Individual changes of this event as published by NVD

   Type	Action	Before	After
   SSVC assessment	removed	{"id":"CVE-2026-111793","role":"CISA Coordinator","options":[{"exploitation":"active"},{"automatable":"no"},{"technicalImpact":"partial"}],"version":"2.0.3","timestamp":"2026-11-10T19:50:15.242846Z"}	—
   SSVC assessment	added	—	{"id":"CVE-2026-111793","role":"CISA Coordinator","options":[{"exploitation":"active"},{"automatable":"no"},{"technicalImpact":"partial"}],"version":"2.0.3","timestamp":"2026-11-10T00:00:00+00:00"}

   Source identifier: 134c704f-9b21-4f2e-91b3-4a467353bcc0

2. 10.11.2026Initial analysis by NVDNVD

   Newly listed as affected:

   • Openwave Webtop Media Transcoder (before 1.1.22.0)

   New references:

   • https://github.com/GISOpenwave/security-advisories-public/blob/main/CAN-2026-2032674.md
   • https://openwave.ai
   • https://jvn.jp/en/vu/JVNVU93403064/
   • https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-111793
   Show 5 original changes

   Individual changes of this event as published by NVD

   Type	Action	Before	After
   Product configuration	added	—	OR *cpe:2.3:a:openwave:webtop_media_transcoder:*:*:*:*:*:*:*:* versions up to (excluding) 1.1.22.0
   Reference type	added	—	MITRE: https://github.com/GISOpenwave/security-advisories-public/blob/main/CAN-2026-2032674.md Types: Third Party Advisory
   Reference type	added	—	MITRE: https://openwave.ai Types: Product
   Reference type	added	—	CISA-ADP: https://jvn.jp/en/vu/JVNVU93403064/ Types: Third Party Advisory
   Reference type	added	—	CISA-ADP: https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-111793 Types: US Government Resource

   Source identifier: nvd@nist.gov

3. 10.11.2026Record modifiedCISA ADP

   CISA assessment (SSVC): exploitation: active, automatable: no

   New references:

   • https://jvn.jp/en/vu/JVNVU93403064/
   • https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-111793
   Show 4 original changes

   Individual changes of this event as published by NVD

   Type	Action	Before	After
   Reference	added	—	https://jvn.jp/en/vu/JVNVU93403064/
   Reference	added	—	https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-111793
   SSVC assessment	removed	{"id":"CVE-2026-111793","role":"CISA Coordinator","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"partial"}],"version":"2.0.3","timestamp":"2026-10-19T15:27:28.876275Z"}	—
   SSVC assessment	added	—	{"id":"CVE-2026-111793","role":"CISA Coordinator","options":[{"exploitation":"active"},{"automatable":"no"},{"technicalImpact":"partial"}],"version":"2.0.3","timestamp":"2026-11-10T19:50:15.242846Z"}

   Source identifier: 134c704f-9b21-4f2e-91b3-4a467353bcc0

4. 10.11.2026CISA KEV entry updated9119a7d8…

   4 individual changes: Date Added, Due Date, Required Action, Vulnerability Name

   Show 4 original changes

   Individual changes of this event as published by NVD

   Type	Action	Before	After
   Date Added	added	—	2026-11-10
   Due Date	added	—	2026-11-10
   Required Action	added	—	2026-11-10
   Vulnerability Name	added	—	2026-11-10

   Source identifier: 9119a7d8-5eab-497f-8521-727c672e3725

5. 19.10.2026Record modifiedCISA ADP

   CISA assessment (SSVC): exploitation: none known, automatable: no

   Show the original change

   Individual changes of this event as published by NVD

   Type	Action	Before	After
   SSVC assessment	added	—	{"id":"CVE-2026-111793","role":"CISA Coordinator","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"partial"}],"version":"2.0.3","timestamp":"2026-10-19T15:27:28.876275Z"}

   Source identifier: 134c704f-9b21-4f2e-91b3-4a467353bcc0

Linked advisories

• Threat Actors Exploit Openwave, Cisco BroadWorks VulnerabilitiesSecurityWeek11.11.2026