PatchSiren

PatchSiren cyber security CVE debrief

CVE-2026-7857 D-Link CVE debrief

A buffer overflow vulnerability was found in D-Link DI-8100 16.07.26A1, affecting the function sprintf of the file /user_group.asp of the component CGI Handler. The manipulation leads to buffer overflow. The attack may be initiated remotely. This vulnerability has been publicly disclosed and may be used by attackers. The vulnerability has a high impact on the system and requires immediate attention. Users should be aware of the vulnerability and take necessary actions to mitigate it.

Vendor
D-Link
Product
DI-8100
CVSS
HIGH 7.3
CISA KEV
Not listed in stored evidence
Original CVE published
2026-05-05
Original CVE updated
2026-07-24
Advisory published
2026-05-05
Advisory updated
2026-07-24

Who should care

Users of D-Link DI-8100, system administrators, security teams, and operators should be aware of this vulnerability and take necessary actions to mitigate it. This includes applying vendor patches or updates, restricting access to the affected system, and monitoring for suspicious activity. It is essential to review compensating controls for exposed systems while remediation is scheduled and verified.

Technical summary

The vulnerability is caused by a buffer overflow in the sprintf function of the /user_group.asp file in the CGI Handler component of D-Link DI-8100 16.07.26A1. This can be exploited remotely, potentially allowing attackers to execute arbitrary code or crash the system. The vulnerability has been publicly disclosed and may be used by attackers. It is essential to apply vendor patches or updates to prevent exploitation.

Defensive priority

High

Recommended defensive actions

  • Apply vendor patches or updates
  • Restrict access to the affected system
  • Monitor for suspicious activity
  • Review compensating controls for exposed systems while remediation is scheduled and verified
  • Check relevant monitoring, detection, and logs for exposed assets that need extra review
  • Track exceptions, retest remediated assets, and close the item only after evidence is documented
  • Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The CVE record was published on 2026-05-05T20:16:41.677Z and was last modified on 2026-07-24T08:10:00.150Z. The vulnerability affects D-Link DI-8100 16.07.26A1. The attack may be initiated remotely. The exploit has been disclosed to the public and may be used. Evidence limits suggest further verification is needed to confirm affected scope and severity. Additional verification and review of system logs are recommended to ensure the vulnerability is properly mitigated.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-7857 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-7857

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-7857 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-7857

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.