Unauthenticated session hijacking via null-byte cookie
Published Jan 9, 2025 · Updated Aug 4, 2026
Improper authentication in SonicOS SSLVPN allows remote attackers to hijack an active VPN session with a crafted session cookie. The getSslvpnSessionFromCookie routine decodes a 44-character Base64 cookie, and its session comparison treats a null byte as success instead of rejecting the mismatch. The SSLVPN service must be enabled and at least one client session active; exploitation exposes that user's VPN identity, configuration, and private routes.
Summary
What happened
Improper authentication in SonicOS SSLVPN allows remote attackers to hijack an active VPN session with a crafted session cookie. The getSslvpnSessionFromCookie routine decodes a 44-character Base64 cookie, and its session comparison treats a null byte as success instead of rejecting the mismatch. The SSLVPN service must be enabled and at least one client session active; exploitation exposes that user's VPN identity, configuration, and private routes.
The record
- CVE
- CVE-2024-53704
- Published
- Jan 9, 2025
- Updated
- Aug 4, 2026
- Vendor
- SonicWall
- Product
- SonicOS
- Classifications
- CWE-287, T1563
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jan 9, 2025CVE publishedPublication date reported by the CVE source.
- Aug 4, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=7.1.1-7058 and older versions
- Affected versionversion=7.1.2-7019
- Affected versionversion=8.0.0-8035
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
View daily counts
| Reporting day | Unique IPs |
|---|---|
| Sep 10, 2026 | 5 |
| Sep 11, 2026 | 1 |
| Sep 12, 2026 | 1 |
| Sep 13, 2026 | Unavailable |
| Sep 14, 2026 | 2 |
| Sep 15, 2026 | Unavailable |
| Sep 16, 2026 | 2 |
Public exploit references
- Bishop Fox crafted swap-cookie proof of conceptfunctional · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Reported exploitation
- CISA Known Exploited Vulnerabilities catalog listingknown exploited catalog
Technologies
Your stack
See the directory against your own environment.
Your stack
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