SonicWall SonicOS SSLVPN Use of Single-factor Authentication Vulnerability
- What it is
- SonicWall SonicOS SSLVPN contains a use of single-factor authentication vulnerability that may allow a user with valid credentials for an alternate authentication method to bypass SAML authentication controls. Successful exploitation may also bypass SAML-enforced multi-factor authentication (MFA).
- Who's affected
- Anyone using SonicWall SonicOS SSLVPN.
- Under attack?
- Yes. CISA added this to its catalog of actively exploited vulnerabilities on Nov 6, 2026.
- What to do
- Install the vendor's security update. If there isn't one yet, apply the vendor's workaround, or stop using the product until it's fixed. CISA lists this as actively exploited, so treat it as urgent.
- Fixed in
- See the vendor's advisory
- Zero-day?
- Yes. CISA listed it as exploited the same day it went public, so attacks began before most people could patch.
- CISA deadline
- Federal agencies must fix this by Nov 20, 2026. Everyone else should treat that as a ceiling, not a target.
- CISA's instruction
- Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
Attack timeline
- Nov 6, 2026Went publicThe flaw was published with its CVE number.
- Nov 6, 2026same dayCISA listed it as exploitedAdded to CISA's Known Exploited Vulnerabilities catalog.
- Nov 20, 2026+14 daysFederal fix deadlineU.S. agencies must have it fixed by this date.
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