Quick answers
- Is CVE-2026-49284 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-49284 being exploited in the wild.
- How severe is CVE-2026-49284?
- High severity, with a CVSS score of 7.1, published 17 July 2026.
- Which products and versions are affected?
- simplesamlphp/simplesamlphp (Packagist) ECOSYSTEM:introduced=2.5.0,fixed=2.5.2; Simplesamlphp < 1.18.6, < 2.4.7, >= 2.5.0-rc1 < 2.5.2, >= 2.5.0, <= 2.5.1.
- Is there a fix for CVE-2026-49284?
- Yes. simplesamlphp/simplesamlphp (Packagist): upgrade to 2.5.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-49284 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-49284?
- Check whether you run simplesamlphp/simplesamlphp (Packagist) or Simplesamlphp at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- simplesamlphp/simplesamlphp (Packagist): upgrade to 2.5.2 or later
composer require simplesamlphp/simplesamlphp:^2.5.2
Technical details
The vulnerability exists in SimpleSAMLphp's SAML Service Provider (SP) Assertion Consumer Service (ACS) path. When an unsigned 'Response/InResponseTo' element is combined with a signed assertion that lacks 'SubjectConfirmationData/InResponseTo', the SP fails to verify that the responding Identity Provider (IdP) matches the 'ExpectedIssuer' stored in the SP state. Instead of rejecting the mismatch, the system logs a warning and continues processing. This allows a response from one trusted IdP to be bound to a session initiated for a different IdP, potentially bypassing IdP-specific routing or 'enable_unsolicited' restrictions. This is particularly critical in multi-tenant environments where different IdPs have different assurance levels. The issue is fixed in versions 1.18.6, 2.4.7, and 2.5.2.
Affected products
- SimpleSAMLphp SimpleSAMLphp < 1.18.6, < 2.4.7, >= 2.5.0-rc1 < 2.5.2
Identifiers
- CVE-2026-49284
- GHSA-q8r6-xj3f-wrrm
Timeline
- 2026-05-29: advisory: GitHub Security Advisory published
- 2026-06-01: patched: Versions 2.4.7 and 2.5.2 released
- 2026-07-17: disclosed: CVE-2026-49284 published to NVD