This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of TP-Link TL-WR940N 3.20.1 Build 2
Noroxi assessment
Priority: Monitor (action score 32/100)
- 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: 0.71% (FIRST EPSS); higher than 52.9% of all records.
- Someone on the same network segment 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.
Low priority for now. 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
This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of TP-Link TL-WR940N 3.20.1 Build 200316 Rel.34392n (5553) routers. Authentication is required to exploit this vulnerability. The specific flaw exists within the httpd service, which listens on TCP port 80 by default. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a fixed-length stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-13992.
- Published
- Mar 28, 2023
- Updated
- Jun 17, 2026
- EPSS
- 0.7% · 52th percentile
- CWE
- CWE-121
Report tools
Action score
32
Monitor
Low priority for now.
- CVSS
- 32 / 40 · 8.0 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.7%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- 8.0
- CNA · zdi
- 6.8
- 1.2 point gap
CVSS:3.0/AV:A/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
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.
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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.
We use this product, ask for helpAffected 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.
| Vendor | Product | CPE |
|---|---|---|
| tp-link | tl-wr940n firmware | cpe:2.3:o:tp-link:tl-wr940n_firmware |
| tp-link | tl-wr940n | cpe:2.3:h:tp-link:tl-wr940n |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- tp-link tl-wr940n firmware3.20.1
Versions reported by the vendor
Affected version ranges reported by the assigning authority (zdi). Independent of NVD's CPE analysis and usually ahead of it.
TP-Link TL-WR940N
- 3.20.1 Build 200316 Rel.34392n (5553)affected
Same product
tp-link: all recordsOther highest-scoring records for the same primary product.
- CVE-2023-33538TP-Link TL-WR940N V2/V4, TL-WR841N V8/V10, and TL-WR740N V1/V2 was discovered to contain a command injection vulnerability via the componentKEV77This week
- CVE-2023-36355TP-Link TL-WR940N V4 was discovered to contain a buffer overflow via the ipStart parameter at /userRpm/WanDynamicIpV6CfgRpm.49Plan
- CVE-2019-6989TP-Link TL-WR940N is vulnerable to a stack-based buffer overflow, caused by improper bounds checking by the ipAddrDispose function.38Monitor
Published before and after this one in the same product
- ← EarlierCVE-2022-0650Mar 28, 2023 · This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of TP-Link TL-WR940N 3.20.1 Build 232Monitor
- ← EarlierCVE-2022-24972Mar 28, 2023 · This vulnerability allows network-adjacent attackers to disclose sensitive information on affected installations of TP-Link TL-WR940N 3.20.126Monitor
- Later →CVE-2022-43635Mar 29, 2023 · This vulnerability allows network-adjacent attackers to disclose sensitive information on affected installations of TP-Link TL-WR940N 6_211126Monitor
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.
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.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
—
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
- CVE-2022-436361 days apartThis vulnerability allows network-adjacent attackers to bypass authentication on affected installations of TP-Link TL-WR940N 6_211111 3.20.135Monitor
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Someone on the same network segment 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
- Adjacent
- Attack complexity
- Low
- Privileges required
- Low
- 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:A/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.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Change log
No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.
References
Vendor advisories and official records. Exploit/PoC links are deliberately left out.