Cyber Resilience

CVE-2021-3275

MediumPublic PoC

Published: 26 March 2021

Published
26 March 2021
Modified
21 November 2024
KEV Added
—
Patch
—
CVSS Score v3.1 6.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
EPSS Score 0.0121 79.4th percentile
Risk Priority 13 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-3275 is a medium-severity Cross-site Scripting (CWE-79) vulnerability in Tp-Link Td-W9977 Firmware. Its CVSS base score is 6.1 (Medium).

Operationally, ranked in the top 20.6% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

Unauthenticated stored cross-site scripting (XSS) exists in multiple TP-Link products including WIFI Routers (Wireless AC routers), Access Points, ADSL + DSL Gateways and Routers, which affects TD-W9977v1, TL-WA801NDv5, TL-WA801Nv6, TL-WA802Nv5, and Archer C3150v2 devices through the improper validation of the…

more

hostname. Some of the pages including dhcp.htm, networkMap.htm, dhcpClient.htm, qsEdit.htm, and qsReview.htm and use this vulnerable hostname function (setDefaultHostname()) without sanitization.

CWE(s)
CWE-79

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

tp-link
td-w9977 firmware
v1_0.1.0_0.9.1_up_boot\(161123\)_2016-11-23_15.36.15
tp-link
tl-wa801nd firmware
v5_us_0.9.1_3.16_up_boot\[170905-rel56404\]
tp-link
tl-wa801n firmware
v6_eu_0.9.1_3.16_up_boot\[200116-rel61815\]
tp-link
tl-wr802n firmware
v4_us_0.9.1_3.17_up_boot\[200421-rel38950\]
tp-link
archer-c3150 firmware
v2_170926

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

CA-8 Penetration Testing
addresses: CWE-79

Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.

SI-10 Information Input Validation
addresses: CWE-79

Validates web inputs to reject script-related content that could produce XSS.

SI-15 Information Output Filtering
addresses: CWE-79

Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.

References