cbcvebase.
CVE-2023-0656
published 2023-03-02

CVE-2023-0656: A Stack-based buffer overflow vulnerability in the SonicOS allows a remote unauthenticated attacker to cause Denial of Service (DoS), which could cause an…

PriorityP278high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
ITWEXPLOITVulnCheck KEV
Exploited in the wild
EPSS
41.32%
98.5th percentile
A Stack-based buffer overflow vulnerability in the SonicOS allows a remote unauthenticated attacker to cause Denial of Service (DoS), which could cause an impacted firewall to crash.

Affected

6 ranges
VendorProductVersion rangeFixed in
sonicwallsonicos<= 7.0.1-5111
sonicwallsonicos<= 7.0.1-5083
sonicwallsonicos<= 6.5.4.4-44v-21-1551
sonicwallsonicos
sonicwallsonicos
sonicwallsonicos

Detection & IOCsextracted from sources · hover to see the quote

path/stats/
path/Security_Services
snort
alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET WEB_SPECIFIC_APPS SonicWall SonicOS Unauthenticated Stack-Based Buffer Overflow (CVE-2023-0656) M1"; flow:established,to_server; urilen:>1024; http.uri; content:"/stats/"; startswith; http.protocol; bsize:>8; reference:url,github.com/BishopFox/CVE-2022-22274_CVE-2023-0656; reference:cve,2023-0656; classtype:attempted-dos; sid:2061253; rev:1; metadata:affected_product SonicWall, attack_target Server, tls_state TLSDecrypt, created_at 2025_04_02, cve CVE_2023_0656, deployment Perimeter, deployment Internal, deployment SSLDecrypt, performance_impact Moderate, confidence High, signature_severity Major, tag Exploit, updated_at 2025_04_02, mitre_tactic_id TA0001, mitre_tactic_name Initial_Access, mitre_technique_id T1190, mitre_technique_name Exploit_Public_Facing_Application; target:dest_ip;)
snort
alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET WEB_SPECIFIC_APPS SonicWall SonicOS Unauthenticated Stack-Based Buffer Overflow (CVE-2023-0656) M2"; flow:established,to_server; urilen:>1024; http.uri; content:"/Security_Services"; startswith; http.protocol; bsize:>8; reference:url,github.com/BishopFox/CVE-2022-22274_CVE-2023-0656; reference:cve,2023-0656; classtype:attempted-dos; sid:2061256; rev:1; metadata:affected_product SonicWall, attack_target Server, tls_state TLSDecrypt, created_at 2025_04_02, cve CVE_2023_0656, deployment Perimeter, deployment Internal, deployment SSLDecrypt, performance_impact Low, confidence High, signature_severity Major, tag Exploit, updated_at 2025_04_02, mitre_tactic_id TA0001, mitre_tactic_name Initial_Access, mitre_technique_id T1190, mitre_technique_name Exploit_Public_Facing_Application; target:dest_ip;)
  • Exploit traffic targets HTTP URI paths starting with /stats/ or /Security_Services with a URI length greater than 1024 bytes and an HTTP protocol field longer than 8 bytes — both conditions must be met simultaneously.
  • CVE-2023-0656 and CVE-2022-22274 share the same vulnerable code pattern; exploit payloads for CVE-2022-22274 also work against /resources/ and /atp/ URI paths, which can be used as additional detection pivot points.
  • Exploitation requires no authentication; any inbound HTTP request from an external host matching the URI and length conditions should be treated as a potential exploit attempt.
  • Successful exploitation may force the device into maintenance mode; monitor for unexpected SonicWall firewall reboots or transitions to maintenance mode as a post-exploitation indicator.
  • Signatures should be deployed at the perimeter and on SSL/TLS-decrypting inspection points, as the exploit may arrive over HTTPS; the ET rules explicitly require TLSDecrypt state.
  • ·The Snort/Suricata rules (sid:2061253, sid:2061256) require TLS inspection to be active (tls_state TLSDecrypt); without SSL/TLS decryption enabled on the sensor, exploit traffic over HTTPS will not be detected.

CVSS provenance

nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
vulncheck7.5HIGH
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