CVE-2020-5135A buffer overflow vulnerability in SonicOS allows a remote attacker to cause Denial of Service (DoS) and potentially execute arbitrary code by sending a malicious request to the firewall.
Updated under an hour ago ()
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It affects SonicWall SonicOS and 1 other product. Add what you run to find out whether that includes you.
CISA lists it as known exploited since Mar 15, 2022; federal agencies had to remediate by Apr 5, 2022, and it is known to be used in ransomware. Treat that date as your deadline.
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A buffer overflow vulnerability in SonicOS allows a remote attacker to cause Denial of Service (DoS) and potentially execute arbitrary code by sending a malicious request to the firewall. This vulnerability affected SonicOS Gen 6 version 6.5.4.7, 6.5.1.12, 6.0.5.3, SonicOSv 6.5.4.v and Gen 7 version 7.0.0.0.
- CVSS
- 9.8 CRITICAL (v3.1, CISA ADP)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Weakness (CWE)
- CWE-120
- Known exploited
- Added to CISA KEV Mar 15, 2022; federal remediation due Apr 5, 2022; known ransomware useApply updates per vendor instructions.
- EPSS (exploitation in the next 30 days)
- 26.87% (percentile 98)
- Assigned by
- sonicwall
- NVD analysis
- Analyzed
- Record last updated
- Oct 21, 2025
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
SonicWall SonicOS sonicwall:sonicos (from the name) | SonicOS 6.5.4.7-79n and earlier; SonicOS 6.5.1.11-4n and earlier; SonicOS 6.0.5.3-93o and earlier; SonicOSv 6.5.4.4-44v-21-794 and earlier; SonicOS 7.0.0.0-1 | CNA record |
sonicwall sonicos sonicwall:sonicos | through 6.0.5.3; from 6.5.0.0 through 6.5.1.11; from 6.5.4.0 through 6.5.4.7; 7.0.0.0 | NVD |
sonicwall sonicosv sonicwall:sonicosv | through 6.5.4.4 | NVD |
References
- https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2020-0010x-refsource-confirm, vendor-advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-5135us-government-resource
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.