CVE-2026-25741
Published: 26 February 2026
Summary
CVE-2026-25741 is a high-severity Incorrect Authorization (CWE-863) vulnerability. Its CVSS base score is 7.1 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 4.7th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
Threat & Defense at a Glance
Threat & Defense Details
Likely Mitigating ControlsAI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Periodic review and update of procedures reduces incorrect authorization implementations over time.
Supervision identifies cases where authorization logic incorrectly permits unauthorized actions.
Defining permitted attribute values and auditing modifications reduces the chance of incorrect authorization outcomes due to tampered or missing labels.
The authorization process and usage restrictions help prevent incorrect authorization for remote access types.
Establishing configuration and connection requirements helps ensure correct rather than incorrect authorization for wireless access.
Establishing connection authorization processes for mobile devices helps ensure authorization decisions are correctly implemented rather than incorrect.
Monitoring account use, notifying on changes, and reviewing accounts for compliance corrects incorrect authorization assignments.
Ensures authorization decisions for external system use are correctly implemented and enforced.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Authorization bypass on public API endpoint enables low-priv cloud user to perform unauthorized billing actions (payment method overwrite via Stripe), directly mapping to remote exploitation of a public-facing application for privilege escalation.
NVD Description
Zulip is an open-source team collaboration tool. Prior to commit bf28c82dc9b1f630fa8e9106358771b20a0040f7, the API endpoint for creating a card update session during an upgrade flow was accessible to users with only organization member privileges. When the associated Stripe Checkout session is…
more
completed, the Stripe webhook updates the organization’s default payment method. Because no billing-specific authorization check is enforced, a regular (non-billing) member can change the organization’s payment method. This vulnerability affected the Zulip Cloud payment processing system, and has been patched as of commit bf28c82dc9b1f630fa8e9106358771b20a0040f7. Self-hosted deploys are no longer affected and no patch or upgrade is required for them.
Deeper analysisAI
CVE-2026-25741 is an authorization bypass vulnerability (CWE-863) in Zulip, an open-source team collaboration tool. Prior to commit bf28c82dc9b1f630fa8e9106358771b20a0040f7, the API endpoint for creating a card update session during the upgrade flow lacked billing-specific authorization checks and was accessible to users with only organization member privileges. This issue affected the Zulip Cloud payment processing system, enabling unauthorized updates via integration with Stripe Checkout sessions and webhooks.
A remote attacker with low privileges, specifically a regular organization member without billing administrator rights, can exploit this vulnerability over the network with low complexity and no user interaction required. By accessing the vulnerable endpoint, the attacker initiates a Stripe Checkout session, completes payment using their own card details, and triggers the Stripe webhook to overwrite the organization's default payment method, resulting in high integrity impact and low availability impact (CVSS v3.1 score of 7.1: AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L).
Zulip has patched the vulnerability as of commit bf28c82dc9b1f630fa8e9106358771b20a0040f7. Self-hosted deployments are unaffected and require no upgrade or patch. Additional details are available in the Zulip security advisory at GHSA-vhhx-84f7-rc8j and the patch commit.
Details
- CWE(s)