CVE-2026-31982 PUBLISHED

Open Redirect in SAML Single Sign-On in Guardian/CMC before 26.2.0

Assigner: Nozomi
Reserved: 10.03.2026 Published: 09.07.2026 Updated: 09.07.2026

An Open Redirect vulnerability was discovered in the SAML Single Sign-On functionality due to insufficient validation of a user-controlled redirection parameter. An unauthenticated attacker can craft a request to the SAML sign-in endpoint and poison the cached SAML redirection for other users who subsequently initiate SAML Single Sign-On, enabling phishing and credential-theft attacks, as well as disrupting SAML authentication for all affected users.

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:L/SC:L/SI:L/SA:L
CVSS Score: 5.3

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	None	Confidentiality	Low
Attack Complexity	Low	Integrity	Low	Integrity	Low
Attack Requirements	None	Availability	Low	Availability	Low
Privileges Required	None
User Interaction	Passive

CVSS 4.0

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L
CVSS Score: 7.1

Attack Vector	Network	Scope	Changed
Attack Complexity	Low	Confidentiality Impact	Low
Privileges Required	None	Integrity Impact	Low
User Interaction	Required	Availability Impact	Low

CVSS 3.1

Product Status

Vendor	Nozomi Networks
Product	Guardian
Versions	Default: unaffected affected from 0 to 26.2.0 (excl.)

Vendor	Nozomi Networks
Product	CMC
Versions	Default: unaffected affected from 0 to 26.2.0 (excl.)

Workarounds

Use internal firewall features to limit access to the web management interface.

Solutions

Upgrade to v26.2.0 or later.

Credits

This issue was found by Andrea Palanca of Nozomi Networks Product Security team during an internal investigation. finder

References

https://security.nozominetworks.com/NN-2026:9-01

Problem Types

CWE-601 URL redirection to untrusted site ('open redirect') CWE

Impacts

CAPEC-194 Fake the Source of Data