CVE-2026-74843
Remote stack buffer overflow in Wavlink CGI enabling RCE
Is CVE-2026-74843 being exploited?
Not confirmed. CVE-2026-74843 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.58% probability of exploitation in the next 30 days.
How severe is CVE-2026-74843?
CVE-2026-74843 is rated Critical with a CVSS score of 9.3. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-74843?
Not known from our data. No patch reference has been recorded for CVE-2026-74843, which is not the same as no patch existing — a fix may have shipped without a tagged reference, or after this record was written. The vendor advisory is the only authority on whether a fix exists, and mitigations may be available regardless.
What does CVE-2026-74843 affect?
CVE-2026-74843 affects Wavlink WN531P3 V250922, Wavlink WN535M1 V250922, lighttpd /cgi-bin/export_pingortrace.cgi. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-74843?
Isolate affected devices, disable remote management, apply vendor firmware when released
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote stack-based buffer overflow via HTTP_COOKIE allows remote code execution, full device compromise and network pivoting.
Immediate action required
- affectedV250922
- affectedV250922
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.