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NVD / CVE Program· CNA sonicwall

CVE-2021-20043: A Heap-based buffer overflow vulnerability in SonicWall SMA100 getBookmarks method allows a remote authenticated attacker to potentially…

HighCVSS 8.8 · v3.1—No exploit No fix recorded

Noroxi assessment

Priority: Plan (action score 42/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 23.2% (FIRST EPSS); higher than 97.8% of all records.
  • Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • According to the record, no fixed version is available yet.
  • Mentioned 2 times in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Add it to your regular patch cycle. Update when a fix is released; follow the vendor's advisory.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

A Heap-based buffer overflow vulnerability in SonicWall SMA100 getBookmarks method allows a remote authenticated attacker to potentially execute code as the nobody user in the appliance. This vulnerability affected SMA 200, 210, 400, 410 and 500v appliances.

Published
Dec 8, 2021
Updated
Jun 16, 2026
EPSS
23.2% · 97th percentile

Report tools

JSON

Action score

42

Plan

Add it to your regular patch cycle.

CVSS
35 / 40 · 8.8 / 10
CISA KEV
0 / 30 · Not listed
EPSS
7 / 30 · 23.2%

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • No fixed version yet

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2021-20043

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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  • 10 scans an hour on the security tools, at most 30 a day (3 a day without an account), an API key and MCP
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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
sonicwallsma 200 firmware
sonicwallsma 200
sonicwallsma 210 firmware
sonicwallsma 210
sonicwallsma 410 firmware
sonicwallsma 410
sonicwallsma 400 firmware
sonicwallsma 400
sonicwallsma 500v firmware
sonicwallsma 500v

Using sma 200 firmware? Add it to your stack and be the first to know about CVEs like this one. (VPN gateway)

Watch new CVEs for sma 200 firmware

When you'll hear from us

  • when a new CVE affecting this product is published
  • when a record in your stack enters KEV or is weaponized

One daily email digest (06:00 UTC); connect a webhook for KEV listings and weaponized exploits every 10 minutes on paid plans, on the hour on the free plan.

Your free account also gets you

  • CVE alerts: add the products and versions you run, get the new CVEs that affect them
  • Uptime monitoring: 1 site, instant email when it goes down
  • Add your domain: subdomains and takeover risk scanned every week (1 domain)
  • 10 scans an hour on the security tools, at most 30 a day (3 a day without an account), an API key and MCP
  • All your scans in one panel: findings, what changed in the last scan, a report per domain or per client (PDF, share link)
All free tools

Sign up with email · Have an account? Sign in

Free account, no card. Unfollow any time.

Versions reported by the vendor

Affected version ranges reported by the assigning authority (sonicwall). Independent of NVD's CPE analysis and usually ahead of it.

  • SonicWall SonicWall SMA100

    • 10.2.0.8-37sv and earlier, 10.2.1.1-19sv and earlier, 10.2.1.2-24sv and earlieraffected

Other highest-scoring records for the same primary product.

  • CVE-2021-20038A Stack-based buffer overflow vulnerability in SMA100 Apache httpd server's mod_cgi module environment variables allows a remote…KEV
    99Now
  • CVE-2023-44221Improper neutralization of special elements in the SMA100 SSL-VPN management interface allows a remote authenticated attacker with…KEV
    81Now
  • CVE-2021-20034An improper access control vulnerability in SMA100 allows a remote unauthenticated attacker to bypass the path traversal checks and delete…
    61This week

Published before and after this one in the same product

  • ← EarlierCVE-2021-20041Dec 8, 2021 · An unauthenticated and remote adversary can consume all of the device's CPU due to crafted HTTP requests sent to SMA100…
    36Monitor
  • ← EarlierCVE-2021-20042Dec 8, 2021 · An unauthenticated remote attacker can use SMA 100 as an unintended proxy or intermediary undetectable proxy to bypass firewall rules.
    40Plan
  • Later →CVE-2021-20044Dec 8, 2021 · A post-authentication remote command injection vulnerability in SonicWall SMA100 allows a remote authenticated attacker to execute OS…
    47Plan

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

No fix version is recorded for this entry. Check the references for vendor advisories.

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

All national notices →

Not on record for this CVE: EPSS history · patch commit or PR link · researcher credit · variant or chain candidate · public bounty program.

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

ATT&CK techniques

—

References

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records