Cyber Posture

CVE-2026-42354

Critical

Published: 08 May 2026

Published
08 May 2026
Modified
08 May 2026
KEV Added
Patch
CVSS Score 9.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS Score 0.0003 8.6th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-42354 is a critical-severity Authentication Bypass by Spoofing (CWE-290) vulnerability. Its CVSS base score is 9.1 (Critical).

Operationally, ranked at the 8.6th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

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.

addresses: CWE-290

Reveals spoofed logon attempts through unexpected previous logon timestamps upon legitimate login.

addresses: CWE-290

Training specifically addresses recognizing spoofed communications and phishing that enable authentication bypass.

addresses: CWE-290

Requiring verifiable identity evidence at appropriate assurance levels makes it substantially harder for attackers to successfully spoof or impersonate users to obtain accounts.

addresses: CWE-290

Unique device authentication makes successful spoofing of device identity substantially more difficult to achieve.

addresses: CWE-290

Unique identification of non-organizational users reduces the feasibility of authentication bypass by spoofing.

addresses: CWE-290

Unique identification and authentication of services before communications makes spoofing of service identities substantially harder.

addresses: CWE-290

Isolated trusted path ensures the user interacts only with genuine system components, preventing spoofing of authentication interfaces or prompts.

addresses: CWE-290

Directly counters DNS response spoofing by requiring cryptographic origin authentication artifacts from the authoritative source.

NVD Description

Sentry is an error tracking and performance monitoring tool. From version 21.12.0 to before version 26.4.1, a critical vulnerability was discovered in the SAML SSO implementation of Sentry. The vulnerability allows an attacker to take over any user account by…

more

using a malicious SAML Identity Provider and another organization on the same Sentry instance. The victim email address must be known in order to exploit this vulnerability. This issue has been patched in version 26.4.1.

Deeper analysisAI

Automated synthesis unavailable for this CVE.

Details

CWE(s)

Affected Products

From
inferred from references and description; NVD did not file a CPE for this CVE

CVEs Like This One

CVE-2025-59707Shared CWE-290
CVE-2026-33661Shared CWE-290
CVE-2026-34457Shared CWE-290
CVE-2025-62235Shared CWE-290
CVE-2025-8853Shared CWE-290
CVE-2026-2800Shared CWE-290
CVE-2018-25316Shared CWE-290
CVE-2026-35622Shared CWE-290
CVE-2025-71056Shared CWE-290
CVE-2025-69203Shared CWE-290

References