CVE-2026-6239Authenticated Stack-based Buffer Overflow in ONVIF CreateUsers Service in TP-Link Tao C520WS
- 6.8MediumCVSS base score
- 0.18%Exploitation in 30 daysEPSS · top 92% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
A stack‑based buffer overflow vulnerability exists in Tapo C520WS v2 in the ONVIF CreateUsers service, where the device fails to properly validate the number of XML user nodes during request processing. An authenticated attacker can send a specially crafted ONVIF request containing an excessive number of user entries to trigger memory corruption. Successful exploitation may cause the ONVIF management service to terminate unexpectedly, resulting in a denial‑of‑service (DoS) condition that disrupts device configuration and management functions.
Timeline
ID reserved
By TPLink
- 53 days later
· 53 days later
Published
- 3 days later
· 3 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| TPLinkCNA (assigner) | 4.0 | Medium6.8 | CVSS:4.0/AV:A/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |
| NVDNVD · Deferred | 4.0 | Medium6.8 | CVSS:4.0/AV:A/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/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 |
- EPSS (exploitation in 30 days)
- 0.18% · top 92% of all CVEs (12 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.8.
Affected products
TP-Link Systems Inc. · Tapo C520WS v2
- affected < 1.2.6 Build 260528
References
References3
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-34934 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-6239)Record last updated .