Sentry: Improper authentication on SAML SSO process allows user identity linking

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

9.1 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

EPSS

• CVE-2026-27197: 0.49% estimated exploitation activity in the next 30 days; percentile 42.49 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Impact A critical vulnerability was discovered in the SAML SSO implementation of Sentry. It was reported to us via our 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. For self-hosted users, you are only vulnerable if the following conditions are met: - You 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 your multo-organization instance.

Patches - Sentry SaaS: The fix was deployed on February 18, 2026. No action is required. - Self-Hosted Sentry: If only a single organization is allowed (SENTRY_SINGLE_ORGANIZATION = True), then no action is needed. We…

Published by the source

17 Apr 2026, 21:25 UTC

Last modified by the source

29 Jun 2026, 12:26 UTC

Source last checked

24 Oct 2026, 04:13 UTC

1. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-ggmg-cqg6-j45g

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# Patch Next advisory brief: CVE-2026-27197

Advisory: Sentry: Improper authentication on SAML SSO process allows user identity linking
IDs: CVE-2026-27197, GHSA-ggmg-cqg6-j45g
Record: https://patchnext.com/advisories/cve-2026-27197 (revision 1, source checked 24 Oct 2026, 04:13 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Critical (CVSS 9.1)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor response not established. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI sentry: affected >= 21.12.0

## Suggested inspection (read-only)
- `python -m pip show sentry`: prints the installed version. Run with the environment that serves production active.

## Supported action
No complete vendor fix is recorded. Follow the primary source's mitigation guidance and check this record again before closing anything.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on sentry.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-ggmg-cqg6-j45g (OSV record GHSA-ggmg-cqg6-j45g lists affected ranges: PyPI sentry >=21.12.0)

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