CVE-2026-42354
Sentry: Improper authentication on SAML SSO process allows user identity linking
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 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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Sentry: Improper authentication on SAML SSO process allows user identity linking
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 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.
- Record
CVE-2026-42354- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - Weakness
- CWE-290
- Updated
- 2026-11-02
EUVDEUVD-2026-28860
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 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.
- Record
EUVD-2026-28860- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-rcmw-7mc7-3rj7
Sentry's improper authentication on SAML SSO process allows user identity linking
Impact
A critical vulnerability was discovered in the SAML SSO implementation of Sentry. It was reported to us via Sentry's private bug bounty program.
The vulnerability allows an attacker to take over any user account by 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.
Self-hosted users are only vulnerable if the following conditions are met:
- They have more than one organization configured (SENTRY_SINGLE_ORGANIZATION = False).
- A malicious user has existing access and permissions to modify SSO settings for another organization in their multi-organization instance.
Patches
- Sentry SaaS: The fix was deployed in April. No action is required.
- Self-Hosted Sentry: If only a single organization is allowed (SENTRY_SINGLE_ORGANIZATION = True), then no action is needed. Sentry recommends upgrading to version 26.4.1 or higher.
Workarounds
User account-based two-factor authentication prevents an attacker from being able to complete authentication with a victim's user account. Organization administrators cannot do this on a user's behalf, this requires individual users to ensure 2FA has been enabled for their account.
Users can manage their two-factor authentication settings through Account Settings > Security page. For step-by-step details, please see the Sentry helpdesk article.
Resources
Please note that this is distinct vulnerability from the similar https://github.com/getsentry/sentry/security/advisories/GHSA-7pq6-v88g-wf3w from 2025.
- Record
GHSA-rcmw-7mc7-3rj7- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - Weakness
- CWE-290
- Updated
- 2026-11-02
NVD
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 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.
- Record
CVE-2026-42354- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-290
- Updated
- 2026-11-02
OSV
Sentry: Improper authentication on SAML SSO process allows user identity linking
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 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.
- Record
CVE-2026-42354- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - Weakness
- CWE-290
- Updated
- 2026-11-02
OSVGHSA-rcmw-7mc7-3rj7
Sentry's improper authentication on SAML SSO process allows user identity linking
Impact
A critical vulnerability was discovered in the SAML SSO implementation of Sentry. It was reported to us via Sentry's private bug bounty program.
The vulnerability allows an attacker to take over any user account by 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.
Self-hosted users are only vulnerable if the following conditions are met:
- They have more than one organization configured (SENTRY_SINGLE_ORGANIZATION = False).
- A malicious user has existing access and permissions to modify SSO settings for another organization in their multi-organization instance.
Patches
- Sentry SaaS: The fix was deployed in April. No action is required.
- Self-Hosted Sentry: If only a single organization is allowed (SENTRY_SINGLE_ORGANIZATION = True), then no action is needed. Sentry recommends upgrading to version 26.4.1 or higher.
Workarounds
User account-based two-factor authentication prevents an attacker from being able to complete authentication with a victim's user account. Organization administrators cannot do this on a user's behalf, this requires individual users to ensure 2FA has been enabled for their account.
Users can manage their two-factor authentication settings through Account Settings > Security page. For step-by-step details, please see the Sentry helpdesk article.
Resources
Please note that this is distinct vulnerability from the similar https://github.com/getsentry/sentry/security/advisories/GHSA-7pq6-v88g-wf3w from 2025.
- Record
GHSA-rcmw-7mc7-3rj7- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - Weakness
- CWE-290
- Updated
- 2026-11-02
OSVPYSEC-2026-534
Sentry's improper authentication on SAML SSO process allows user identity linking
Impact
A critical vulnerability was discovered in the SAML SSO implementation of Sentry. It was reported to us via Sentry's private bug bounty program.
The vulnerability allows an attacker to take over any user account by 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.
Self-hosted users are only vulnerable if the following conditions are met:
- They have more than one organization configured (SENTRY_SINGLE_ORGANIZATION = False).
- A malicious user has existing access and permissions to modify SSO settings for another organization in their multi-organization instance.
Patches
- Sentry SaaS: The fix was deployed in April. No action is required.
- Self-Hosted Sentry: If only a single organization is allowed (SENTRY_SINGLE_ORGANIZATION = True), then no action is needed. Sentry recommends upgrading to version 26.4.1 or higher.
Workarounds
User account-based two-factor authentication prevents an attacker from being able to complete authentication with a victim's user account. Organization administrators cannot do this on a user's behalf, this requires individual users to ensure 2FA has been enabled for their account.
Users can manage their two-factor authentication settings through Account Settings > Security page. For step-by-step details, please see the Sentry helpdesk article.
Resources
Please note that this is distinct vulnerability from the similar https://github.com/getsentry/sentry/security/advisories/GHSA-7pq6-v88g-wf3w from 2025.
- Record
PYSEC-2026-534- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
sentryPyPI |
21.12.0 to 26.4.0 | 26.4.1 |
sentryPyPI |
21.12.0 up to 26.4.1, plus listed versions 22.1.022.10.022.11.022.12.022.2.0 Show 21 moreShow less22.3.022.4.022.5.022.6.022.7.022.8.022.9.023.1.023.1.123.2.023.3.023.3.123.4.023.5.023.5.123.5.223.6.023.6.123.6.223.7.023.7.1 |
26.4.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-42354 is a critical vulnerability (CVSS 9.1) in Getsentry Sentry, published April 30, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.62%, the 50th percentile. Fixed in sentry 26.4.1.
References
github.com/getsentry/sentry/security/advisories/GHSA-rcmw-7mc7-3rj7
nvd.nist.gov/vuln/detail/CVE-2026-42354
pypi.org/project/sentry