Tenda AC20 HTTP POST Request SetPptpServerCfg strcpy buffer overflow

published 2025-09-22 13 mo ago modified 2026-10-11 28 d ago also EUVD-2025-30473

cvss: 8.8; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.9%; EPSS 0.9% chance of exploitation in 30 days, percentile 59%
public exploits: 0; none known

A vulnerability was identified in Tenda AC20 up to 16.03.08.12. Affected by this issue is the function strcpy of the file /goform/SetPptpServerCfg of the component HTTP POST Request Handler. Such manipulation of the argument startIp leads to buffer overflow. The attack can be launched remotely. The exploit is publicly available and might be used.

CISA SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: total
Assessed: 13 mo ago (2025-09-23)

Exploit prediction

0.88% chance of exploitation in the next 30 days, higher than 59% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/Juana-2u/Tenda-AC20 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	4.0	8.7	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P
CNA	3.1	8.8	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:R
CNA	3.0	8.8	CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:R
CNA	2.0	9.0	AV:N/AC:L/Au:S/C:C/I:C/A:C/E:POC/RL:ND/RC:UR
CNA	4.0	7.4	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/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
CNA	3.1	8.8	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CNA	2.0	9.0	AV:N/AC:L/Au:S/C:C/I:C/A:C

Affected products

Tenda AC20

Classification

Weakness

CWE-120 Buffer Copy without Checking Size of Input
CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer

References

github.com /Juana-2u/Tenda-AC20
exploit, not-applicable
vuldb.com /?id.325173
vdb-entry, technical-description, third-party-advisory
vuldb.com /?ctiid.325173
signature, permissions-required, vdb-entry
vuldb.com /?submit.654460
third-party-advisory, vdb-entry
tenda.com.cn /
product

Sources

CVE List CVE-2025-10815
NVD CVE-2025-10815

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary