How severe is CVE-2026-6240?

CVE-2026-6240 has a CVSS 4.0 base score of 6.8, rated medium severity.

Is CVE-2026-6240 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (8th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-6240?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-6240 have an EU (EUVD) identifier?

Yes. CVE-2026-6240 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-34935.

When was CVE-2026-6240 published?

CVE-2026-6240 was published on 2026-06-06 and last updated on 2026-06-17.

CVE-2026-6240

CVE-2026-6240 is a medium-severity vulnerability with a CVSS 4.0 base score of 6.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-121.

Key facts

Severity: Medium (CVSS 4.0 base score 6.8)
EPSS exploit prediction: 0% (8th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-34935
Weakness: CWE-121
Published: 2026-06-06
Last modified: 2026-06-17

Description

A stack-based buffer overflow vulnerability exists in Tapo C520WS v2 in the ONVIF DeleteUsers service, due to insufficient boundary checks when handling multiple user deletion parameters. An authenticated attacker can send a crafted malicious request containing an excessive number of identifiers to overflow stack memory. Successful exploitation may result in a service crash or deadlock, leading to DoS affecting device management and monitoring functionality.

Frequently asked questions

What is CVE-2026-6240?: A stack-based buffer overflow vulnerability exists in Tapo C520WS v2 in the ONVIF DeleteUsers service, due to insufficient boundary checks when handling multiple user deletion parameters. An authenticated attacker can send a crafted malicious request containing an excessive number of identifiers to overflow stack memory. Successful exploitation may result in a service crash or deadlock, leading to DoS affecting device management and monitoring functionality.
How severe is CVE-2026-6240?: CVE-2026-6240 has a CVSS 4.0 base score of 6.8, rated medium severity.
Is CVE-2026-6240 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (8th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-6240?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-6240 have an EU (EUVD) identifier?: Yes. CVE-2026-6240 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-34935.
When was CVE-2026-6240 published?: CVE-2026-6240 was published on 2026-06-06 and last updated on 2026-06-17.

References

Other CWE-121 (Stack-based Buffer Overflow) vulnerabilities

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