CVE-2026-25741Network attack vector

Payment-method modification via missing billing authorization

Published Feb 26, 2026 · Updated Feb 26, 2026

Incorrect authorization in Zulip Cloud allows remote authenticated users to change an organization's default payment method. The start_card_update_stripe_session_for_realm_upgrade endpoint used require_organization_member instead of require_billing_access before creating a Stripe card-update session. Any regular organization member could complete the linked checkout flow, causing the webhook to replace the default payment method; self-hosted deployments were not affected.

CVSS severity7.1
High
EPSS probability0.27%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Incorrect authorization in Zulip Cloud allows remote authenticated users to change an organization's default payment method. The start_card_update_stripe_session_for_realm_upgrade endpoint used require_organization_member instead of require_billing_access before creating a Stripe card-update session. Any regular organization member could complete the linked checkout flow, causing the webhook to replace the default payment method; self-hosted deployments were not affected.

The record

CVE
CVE-2026-25741
Published
Feb 26, 2026
Updated
Feb 26, 2026
Vendor
Zulip
Product
Zulip
Classifications
CWE-863, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 26, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 26, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< bf28c82dc9b1f630fa8e9106358771b20a0040f7

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Zulip · Zulipversion=< bf28c82dc9b1f630fa8e9106358771b20a0040f7

Published CVSS scores

7.1GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-863Incorrect Authorization
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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