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TI-2021-19856 Aliases CVE-2021-44158GHSA-m8r5-j3fq-hx58

ASUS RT-AX56U Router - Stack-based buffer overflow

Priority LOW 36CWE-121Published · Updated

Key facts

Attack vector
Adjacent network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-121 and the CVSS impact.

Summary

ASUS RT-AX56U Wi-Fi Router is vulnerable to stack-based buffer overflow due to improper validation for httpd parameter length. An authenticated local area network attacker can launch arbitrary code execution to control the system or disrupt service.

Why it matters now

EPSS 0.00699 53rd percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
ASUSRT-AX56U3.0.0.4.386.44266—No fix listedCNA
  • RT-AX56U VendorASUS Affected 3.0.0.4.386.44266 Fixed in — No fix listed CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:o:asus:rt-ax56u_firmware:3.0.0.4.386.44266:*:*:*:*:*:*:*3.0.0.4.386.44266VulnerableASUS
cpe:2.3:h:asus:rt-ax56u:-:*:*:*:*:*:*:*not specified by NVDRunning onASUS
  • cpe:2.3:o:asus:rt-ax56u_firmware:3.0.0.4.386.44266:*:*:*:*:*:*:* Versions 3.0.0.4.386.44266 Vulnerable ·ASUS
  • cpe:2.3:h:asus:rt-ax56u:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·ASUS

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-44158
  2. 2026-10-03 Alias added: GHSA-m8r5-j3fq-hx58

References

Advisory 1

  • TI-2022-09749 Out-of-bounds write in Asuswrt-Merlin New Gen CVSS 3.1CRITICAL 9.8
  • TI-2021-18228 A brute-force protection bypass in CAPTCHA protection in ASUS ROG Rapture GT-AX11000… CVSS 3.1CRITICAL 9.8
  • TI-2021-02220 In ASUS RT-AX3000, ZenWiFi AX (XT8), RT-AX88U, and other ASUS routers with firmware <… CVSS 3.1HIGH 7.5
  • TI-2021-19533 ASUS RT-A88U 3.0.0.4.386_45898 is vulnerable to Cross Site Scripting (XSS). CVSS 3.1CRITICAL 9.0
  • TI-2021-18229 An HTTP request smuggling in web application in ASUS ROG Rapture GT-AX11000, RT-AX3000… CVSS 3.1HIGH 7.5
  • TI-2021-17582 A stack overflow vulnerability exists in the httpd service in ASUS RT-AX56U Router… CVSS 3.1HIGH 8.8
See all 11 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences