D-Link DIR-823X Login sub_40AC74 excessive authentication
A vulnerability was identified in D-Link DIR-823X 250416. This vulnerability affects the function sub_40AC74 of the component Login. Such manipulation leads to improper restriction of excessive authentication attempts. The attack may be performed from remote. This attack is characterized by high complexity. It is stated that the exploitability is difficult. The exploit is publicly available and might be used.
- Published
- Jan 30, 2026
- Updated
- Jun 17, 2026
- EPSS
- 1.2% · 66th percentile
- CWE
- CWE-307
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Report tools
Action score
11
Monitor
Low priority for now.
- CVSS
- 11 / 40 · 2.9 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 1.2%
CISA SSVC decision
- Exploitation
- proof of concept
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- —
- CNA · VulDB
- 6.3
- NVD has not scored this yet; the score shown is the CNA’s.
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
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 |
|---|---|---|
| dlink | dir-823x firmware | cpe:2.3:o:dlink:dir-823x_firmware |
| dlink | dir-823x | cpe:2.3:h:dlink:dir-823x |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- dlink dir-823x firmware250416
Versions reported by the vendor
Affected version ranges reported by the assigning authority (VulDB). Independent of NVD's CPE analysis and usually ahead of it.
D-Link DIR-823X
- 250416affected
Same product
dlink: all recordsOther highest-scoring records for the same primary product.
- CVE-2025-29635A command injection vulnerability in D-Link DIR-823X 240126 and 240802 allows an authorized attacker to execute arbitrary commands on remoteKEV84Now
- CVE-2025-29043An issue in dlink DIR 832x 240802 allows a remote attacker to execute arbitrary code via the function 0x41723440Plan
- CVE-2025-29042An issue in dlink DIR 832x 240802 allows a remote attacker to execute arbitrary code via the macaddr key value to the function 0x42232c40Plan
- CVE-2024-39962D-Link DIR-823X AX3000 Dual-Band Gigabit Wireless Router v21_D240126 was discovered to contain a remote code execution (RCE) vulnerability i40Plan
- CVE-2025-29041An issue in dlink DIR 823x 240802 allows a remote attacker to execute arbitrary code via the target_addr key value and the function 0x41710c39Monitor
- CVE-2025-29040An issue in dlink DIR 823x 240802 allows a remote attacker to execute arbitrary code via the target_addr key value and the function 0x41737c39Monitor
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.
- 942384053 (VulDB User)reporter
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.
- Special conditions such as timing or configuration are required.
If successful
- Confidentiality
- Integrity
- Availability
- Attack vector
- Network
- Attack complexity
- High
- Privileges required
- None
- User interaction
- None
- Scope
- X
Weakness class (CWE)
CWE-307 · Improper Restriction of Excessive Authentication AttemptsCVSS vector
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
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.
Attack patterns (CAPEC)
- Dictionary-based Password AttackCAPEC-16likelihood: Medium · High
- Password Brute ForcingCAPEC-49likelihood: Medium · High
- Use of Known Domain CredentialsCAPEC-560likelihood: High · High
- Password SprayingCAPEC-565likelihood: High · High
- Credential StuffingCAPEC-600likelihood: High · High
- Use of Known Kerberos CredentialsCAPEC-652likelihood: Medium · High
- Use of Known Operating System CredentialsCAPEC-653likelihood: High · High
Change log
No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.
References
- github.com/master-abc/cve/issues/17
- vuldb.com/?ctiid.343479
- vuldb.com/?id.343479
- vuldb.com/?submit.740886
- www.dlink.com/
Vendor advisories and official records. Exploit/PoC links are deliberately left out.