Description
Element Call is a native Matrix video conferencing application. Versions 0.5.17 through 0.19.3 report analytics data to a PostHog server, when configured to by a `posthog` key in config.json or by the `posthogApiHost` and `posthogApiKey` URL parameters. Several fields of this data (`$initial_person_info`, `$session_entry_url`, and `$current_url`) were found to contain the full URL of the user's visited page, including the fragment. Users of a standalone Element Call ‘SPA’ instance such as https://call.element.io may therefore have reported the full URLs of certain calls, including encryption passwords, to the configured PostHog server, potentially compromising the confidentiality of the calls to actors who could access both the PostHog analytics data and the encrypted media streams. The same issue is present in Element Call's embedded package, but in practice it does not impact applications using this package (including Element Web, Element Desktop, Element X iOS, and Element X Android) because they distribute encryption keys over Matrix rather than encoding a password in the URL. The issue is patched in Element Call 0.19.4. Some workarounds are available. Users may opt out of analytics in the 'Feedback' tab of Element Call's settings and create new links for future calls. Admins who host Element Call as a standalone application may disable PostHog analytics entirely by removing the `posthog` key from their deployment's config.json file.
Published: 2026-08-07
Score: 8.6 High
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

Impact

A flaw in Element Call versions 0.5.17 through 0.19.3 causes analytics data to include the full URL of a user's visited page, which may contain an encryption password. The data is sent to a PostHog server when analytics are enabled, leaking sensitive call information that could allow an attacker who can read the analytics stream to compromise the confidentiality of the encrypted media. This is an information‑disclosure weakness (CWE‑200).

Affected Systems

The issue is limited to standalone Element Call installations, such as https://call.element.io, that use the posthog key or the posthogApiHost and posthogApiKey URL parameters. Embedded Element Call packages used within Element Web, Desktop, and mobile applications are not affected because they transmit encryption keys through the Matrix protocol rather than within URLs. Affected versions range from 0.5.17 to 0.19.3; the vulnerability is patched in 0.19.4.

Risk and Exploitability

The CVSS score of 8.6 marks this as a high‑severity vulnerability, and while EPSS is not available, the lack of a KEV listing does not reduce the potential impact. Exploitation requires that analytics be enabled and the relevant key present; an attacker can influence a user’s URL or rely on an administrator’s misconfiguration to cause sensitive data to be sent to the analytics server. The primary attack vector is via the analytics configuration, either through user‑controlled links or server‑side misconfiguration, and the exploitation would result in disclosure of call encryption passwords.

Generated by OpenCVE AI on August 7, 2026 at 20:20 UTC.

Remediation

No vendor fix or workaround currently provided.

OpenCVE Recommended Actions

  • Update Element Call to version 0.19.4 or later to apply the official fix.
  • If an upgrade cannot be performed immediately, disable PostHog analytics by removing the posthog key, or the posthogApiHost and posthogApiKey parameters, from the deployment’s config.json file or via the administration settings.
  • Users can opt out of analytics in the Feedback tab of Element Call’s settings and generate new call links that do not contain sensitive data.

Generated by OpenCVE AI on August 7, 2026 at 20:20 UTC.

Tracking

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Advisories
Source ID Title
Github GHSA Github GHSA GHSA-6vhh-4xw6-h2h2 Element Call reports full URLs of visited pages to analytics server
History

Fri, 07 Aug 2026 19:45:00 +0000

Type Values Removed Values Added
Description Element Call is a native Matrix video conferencing application. Versions 0.5.17 through 0.19.3 report analytics data to a PostHog server, when configured to by a `posthog` key in config.json or by the `posthogApiHost` and `posthogApiKey` URL parameters. Several fields of this data (`$initial_person_info`, `$session_entry_url`, and `$current_url`) were found to contain the full URL of the user's visited page, including the fragment. Users of a standalone Element Call ‘SPA’ instance such as https://call.element.io may therefore have reported the full URLs of certain calls, including encryption passwords, to the configured PostHog server, potentially compromising the confidentiality of the calls to actors who could access both the PostHog analytics data and the encrypted media streams. The same issue is present in Element Call's embedded package, but in practice it does not impact applications using this package (including Element Web, Element Desktop, Element X iOS, and Element X Android) because they distribute encryption keys over Matrix rather than encoding a password in the URL. The issue is patched in Element Call 0.19.4. Some workarounds are available. Users may opt out of analytics in the 'Feedback' tab of Element Call's settings and create new links for future calls. Admins who host Element Call as a standalone application may disable PostHog analytics entirely by removing the `posthog` key from their deployment's config.json file.
Title Element Call reports full URLs of visited pages to analytics server
Weaknesses CWE-200
References
Metrics cvssV4_0

{'score': 8.6, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N'}

Subscriptions

No data.

cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-08-07T19:32:00.068Z

Reserved: 2026-05-20T17:44:09.586Z

Link: CVE-2026-48007

cve-icon Vulnrichment

No data.

cve-icon NVD

No data.

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-07T20:30:17Z

Weaknesses
  • CWE-200

    Exposure of Sensitive Information to an Unauthorized Actor