A Stack-based buffer overflow vulnerability in SMA100 Apache httpd server's mod_cgi module environment variables allows a remote unauthentic
A Stack-based buffer overflow vulnerability in SMA100 Apache httpd server's mod_cgi module environment variables allows a remote unauthenticated attacker to potentially execute code as a 'nobody' user in the appliance. This vulnerability affected SMA 200, 210, 400, 410 and 500v appliances firmware 10.2.0.8-37sv, 10.2.1.1-19sv, 10.2.1.2-24sv and earlier versions.
- Published
- Dec 8, 2021
- Updated
- Jun 16, 2026
- EPSS
- 99.9% · 100th percentile
- CWE
- CWE-121
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Report tools
Action score
99
Now
Patch today or shut off access.
- CVSS
- 39 / 40 · 9.8 / 10
- CISA KEV
- 30 / 30 · Listed
- EPSS
- 30 / 30 · 99.9%
CISA SSVC decision
- Exploitation
- active
- Automatable
- yes
- Technical impact
- total
Vulnrichment: CISA's decision-tree inputs.
Actively exploited in the wild
CISA added this to its Known Exploited Vulnerabilities catalog on Jan 28, 2022. That signals real attacks, not theory.
Remediation deadline for government agencies: Feb 11, 2022.
Known to be used in ransomware campaigns.
Affected systems
| Vendor | Product | CPE |
|---|---|---|
| sonicwall | sma 200 firmware | cpe:2.3:o:sonicwall:sma_200_firmware |
| sonicwall | sma 200 | cpe:2.3:h:sonicwall:sma_200 |
| sonicwall | sma 210 firmware | cpe:2.3:o:sonicwall:sma_210_firmware |
| sonicwall | sma 210 | cpe:2.3:h:sonicwall:sma_210 |
| sonicwall | sma 410 firmware | cpe:2.3:o:sonicwall:sma_410_firmware |
| sonicwall | sma 410 | cpe:2.3:h:sonicwall:sma_410 |
| sonicwall | sma 400 firmware | cpe:2.3:o:sonicwall:sma_400_firmware |
| sonicwall | sma 400 | cpe:2.3:h:sonicwall:sma_400 |
| sonicwall | sma 500v firmware | cpe:2.3:o:sonicwall:sma_500v_firmware |
| sonicwall | sma 500v | cpe:2.3:h:sonicwall:sma_500v |
Using sma 200 firmware? Add it to your stack and be the first to know about CVEs like this one. (VPN gateway)
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- sonicwall sma 200 firmware10.2.0.8-37sv
- sonicwall sma 200 firmware10.2.1.1-19sv
- sonicwall sma 200 firmware10.2.1.2-24sv
- sonicwall sma 210 firmware10.2.0.8-37sv
- sonicwall sma 210 firmware10.2.1.1-19sv
- sonicwall sma 210 firmware10.2.1.2-24sv
- sonicwall sma 400 firmware10.2.0.8-37sv
- sonicwall sma 400 firmware10.2.1.1-19sv
- sonicwall sma 400 firmware10.2.1.2-24sv
- sonicwall sma 410 firmware10.2.0.8-37sv
- sonicwall sma 410 firmware10.2.1.1-19sv
- sonicwall sma 410 firmware10.2.1.2-24sv
- sonicwall sma 500v firmware10.2.0.8-37sv
- sonicwall sma 500v firmware10.2.1.1-19sv
- sonicwall sma 500v firmware10.2.1.2-24sv
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
Same product
sonicwall: all recordsOther highest-scoring records for the same primary product.
- CVE-2023-44221Improper neutralization of special elements in the SMA100 SSL-VPN management interface allows a remote authenticated attacker with administrKEV81Now
- CVE-2021-20034An improper access control vulnerability in SMA100 allows a remote unauthenticated attacker to bypass the path traversal checks and delete a60This week
- CVE-2021-20039Improper neutralization of special elements in the SMA100 management interface '/cgi-bin/viewcert' POST http method allows a remote authenti59Plan
- CVE-2021-20035Improper neutralization of special elements in the SMA100 management interface allows a remote authenticated attacker to inject arbitrary coKEV57Plan
- CVE-2021-20045A buffer overflow vulnerability in SMA100 sonicfiles RAC_COPY_TO (RacNumber 36) method allows a remote unauthenticated attacker to potential47Plan
- CVE-2021-20044A post-authentication remote command injection vulnerability in SonicWall SMA100 allows a remote authenticated attacker to execute OS system47Plan
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
Weaponized
A ready exploit tool or active in-the-wild use is known for this vulnerability. This should be your top priority.
Evidence
- Nuclei detection template ×1
- Proof-of-concept repository on GitHub ×3
Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.
| Source | Kind | Date |
|---|---|---|
| Nuclei detection template | Nuclei template CVE-2021-20038 | — |
| Proof-of-concept repository on GitHub | stars:95 | 2022-01-11 |
| Proof-of-concept repository on GitHub | stars:1 | 2022-08-08 |
| Proof-of-concept repository on GitHub | stars:0 | 2026-02-23 |
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.
- Published
- First PoC+34 d
- CISA KEV+51 d
- TodaySep 29, 2026+1757 d
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- 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
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
CWE-121 · Stack-based Buffer OverflowCVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/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.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for all 385,000+ vulnerabilities; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpChange log
No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.
References
- psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0026
- www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-20038
Vendor advisories and official records. Exploit/PoC links are deliberately left out.