CVE-2026-42354Network attack vector

Account takeover via unbound SSO identity linking

Published May 8, 2026 · Updated May 8, 2026

Authentication bypass in Sentry 21.12.0 through 26.4.0 allows remote authenticated users to take over user accounts through SAML SSO. The SSO setup pipeline passes the IdP-asserted email to identity resolution instead of binding the new identity to the authenticated administrator. Exploitation requires a multi-organization instance, SENTRY_SINGLE_ORGANIZATION=False, SSO-setting access in another organization, an attacker-controlled IdP, and the victim's email address.

CVSS severity9.1
Critical
EPSS probability0.62%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authentication bypass in Sentry 21.12.0 through 26.4.0 allows remote authenticated users to take over user accounts through SAML SSO. The SSO setup pipeline passes the IdP-asserted email to identity resolution instead of binding the new identity to the authenticated administrator. Exploitation requires a multi-organization instance, SENTRY_SINGLE_ORGANIZATION=False, SSO-setting access in another organization, an attacker-controlled IdP, and the victim's email address.

The record

CVE
CVE-2026-42354
Published
May 8, 2026
Updated
May 8, 2026
Vendor
Sentry
Product
Sentry
Classifications
CWE-290, T1078
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. May 8, 2026CVE publishedPublication date reported by the CVE source.
  2. May 8, 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=>= 21.12.0, < 26.4.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Sentry · Sentryversion=>= 21.12.0, < 26.4.1

Published CVSS scores

9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.1GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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-290Authentication Bypass by Spoofing
T1078Valid Accounts

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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