Sonicos
CVE-2026-0400
MEDIUM
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A05:2025 - Injection
ASVS 5.0
V1 - Encoding and Sanitization Format string safety
|
| Impact | CVSS 4.9 (MEDIUM). Attack vector: Network. Complexity: Low. Privileges required: High. User interaction: None. Exploitable via remote/network. |
| Exploit ScenarioDerived | A remote attacker could exploit this vulnerability to compromise the affected system. |
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Alert meAnalysisAIv1 – Mar 12, 2026
SonicOS firewalls are vulnerable to a post-authentication format string vulnerability that permits authenticated remote attackers to trigger a denial of service condition and crash the affected device. The attack requires valid credentials but can be executed over the network without user interaction. No patch is currently available for this vulnerability.
Earlier versions of this analysis (1)
A post-authentication Format String vulnerability in SonicOS allows a remote attacker to crash a firewall. [CVSS 4.9 MEDIUM]
RemediationAI
Monitor vendor advisories for a patch. Restrict network access to the affected service where possible.
Affects your stack
Find out whether the stacks and servers you run are on an affected version.
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
Classified as CWE-134 (Use of Externally-Controlled Format String). Affects Sonicos. A post-authentication Format String vulnerability in SonicOS allows a remote attacker to crash a firewall.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionCVE.org
A post-authentication Format String vulnerability in SonicOS allows a remote attacker to crash a firewall.
Executive ViewAI
Organizations using A post-authentication Format String vulnerability in SonicOS should be aware of moderate risk from CVE-2026-0400 rated CVSS 4.9. Exploitation could compromise the security of affected deployments. Organizations should apply vendor updates when available and monitor for exploitation.
Apply vendor patch. If patching is delayed: restrict network access and enable monitoring.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.
Affected Products (CPE)CVE.org
SonicWall SonicOS SSLVPN contains an authentication bypass vulnerability allowing remote attackers to bypass authenticat
An improper access control vulnerability has been identified in the SonicWall SonicOS management access, potentially lea
An OpenSSL TLS server may crash if sent a maliciously crafted renegotiation ClientHello message from a client. Rated med
RADIUS Protocol under RFC 2865 is susceptible to forgery attacks by a local attacker who can modify any valid Response (
Wind River VxWorks has a Buffer Overflow in the TCP component (issue 1 of 4). Rated critical severity (CVSS 9.8), this v
Wind River VxWorks 6.6 through vx7 has Session Fixation in the TCP component. Rated high severity (CVSS 7.5), this vulne
The X509_V_FLAG_X509_STRICT flag enables additional security checks of the certificates present in a certificate chain.
A Host Header Redirection vulnerability in SonicOS potentially allows a remote attacker to redirect firewall management
An improper authentication vulnerability has been identified in SonicWall SonicOS SSL-VPN feature, which in specific con
A Stack-based buffer overflow vulnerability in the SonicOS via HTTP request allows a remote unauthenticated attacker to
A buffer overflow vulnerability in SonicOS allows a remote attacker to cause Denial of Service (DoS) and potentially exe
Wind River VxWorks 6.7 though 6.9 and vx7 has a Buffer Overflow in the TCP component (issue 3 of 4). Rated critical seve
NVD
CVE.org
EPSS
GitHub PoC
Exploit-DB