A stack buffer overflow vulnerability exists in the ToToLink LR1200GB (V9.1.0u.6619_B20230130) and NR1800X (V9.1.0u.6681_B20230703) Router f
A stack buffer overflow vulnerability exists in the ToToLink LR1200GB (V9.1.0u.6619_B20230130) and NR1800X (V9.1.0u.6681_B20230703) Router firmware within the cstecgi.cgi binary (setDefResponse function). The binary reads the "IpAddress" parameter from a web request and copies it into a fixed-size stack buffer using strcpy() without any length validation. Maliciously crafted input can overflow the buffer, leading to potential arbitrary code execution or memory corruption, without requiring authentication.
- Published
- Nov 13, 2025
- Updated
- Jul 5, 2026
- EPSS
- 0.5% · 42th percentile
- CWE
- CWE-121
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Report tools
Action score
26
Monitor
Low priority for now.
- CVSS
- 26 / 40 · 6.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.5%
CISA SSVC decision
- Exploitation
- proof of concept
- Automatable
- no
- Technical impact
- total
Vulnrichment: CISA's decision-tree inputs.
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for the hundreds of thousands of vulnerabilities in the database; 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 helpAffected systems
| Vendor | Product | CPE |
|---|---|---|
| totolink | lr1200gb firmware | cpe:2.3:o:totolink:lr1200gb_firmware |
| totolink | lr1200gb | cpe:2.3:h:totolink:lr1200gb |
| totolink | nr1800x firmware | cpe:2.3:o:totolink:nr1800x_firmware |
| totolink | nr1800x | cpe:2.3:h:totolink:nr1800x |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- totolink lr1200gb firmware9.1.0u.6619_b20230130
- totolink nr1800x firmware9.1.0u.6681_b20230703
Same product
totolink: all recordsOther highest-scoring records for the same primary product.
- CVE-2023-46977TOTOLINK LR1200GB V9.1.0u.6619_B20230130 was discovered to contain a stack overflow via the password parameter in the function loginAuth.42Plan
- CVE-2024-1783Totolink LR1200GB Web Interface cstecgi.cgi loginAuth stack-based overflow40Plan
- CVE-2024-0295Totolink LR1200GB cstecgi.cgi setWanCfg os command injection40Plan
- CVE-2024-0294Totolink LR1200GB cstecgi.cgi setUssd os command injection40Plan
- CVE-2024-0293Totolink LR1200GB cstecgi.cgi setUploadSetting os command injection40Plan
- CVE-2024-0292Totolink LR1200GB cstecgi.cgi setOpModeCfg os command injection40Plan
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.
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.
- CVE-2025-606840 days apartA stack buffer overflow vulnerability exists in the ToToLink LR1200GB (V9.1.0u.6619_B20230130) and NR1800X (V9.1.0u.6681_B20230703) Router f26Monitor
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
- low · data can be read
- Integrity
- none
- Availability
- low · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- Low
- Integrity impact
- None
- Availability impact
- Low
Weakness class (CWE)
CWE-121 · Stack-based Buffer OverflowCVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L
nvd-secondary
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.