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CVE Record

CVE-2021-41436: An HTTP request smuggling in web application in ASUS ROG Rapture GT-AX11000, RT-AX3000, RT-AX55, RT-AX56U,...

An HTTP request smuggling in web application in ASUS ROG Rapture GT-AX11000, RT-AX3000, RT-AX55, RT-AX56U, RT-AX56U_V2, RT-AX58U, RT-AX82U, RT-AX82U GUNDAM EDITION, RT-AX86 Series(RT-AX86U/RT-AX86S), RT-AX86U ZAKU II EDITION, RT-AX88U, RT-AX92U, TUF Gaming AX3000, TUF Gaming AX5400 (TUF-AX5400), ASUS ZenWiFi XD6, ASUS ZenWiFi AX (XT8) before 3.0.0.4.386.45898, and RT-AX68U before 3.0.0.4.386.45911, allows a remote unauthenticated attacker to DoS via sending a specially crafted HTTP packet.

UnknownCVSS not scoredNot KEV-listedUpdated
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Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

Certain ASUS Wi-Fi routers and mesh systems can be crashed or made unavailable through a crafted HTTP request. The issue is remote and does not require authentication, but the public source bundle only states denial of service, not data theft or device takeover.

Executive priority

Treat this as a moderate operational availability risk for affected ASUS network edge devices. Prioritize firmware verification for internet-facing, remote-managed, branch-office, and executive-home routers because outage impact can exceed the technical severity score, which is not provided in the bundle.

Technical view

CVE-2021-41436 is an HTTP request smuggling flaw in the web application of multiple ASUS router models. A remote unauthenticated attacker can cause denial of service with a specially crafted HTTP packet. Fixed firmware thresholds are 3.0.0.4.386.45898 for most listed models and 3.0.0.4.386.45911 for RT-AX68U.

Likely exposure

Exposure is likely where affected ASUS models remain on firmware earlier than the listed fixed versions. The source bundle does not clarify whether exploitation requires access to a LAN-facing or internet-exposed web interface.

Exploitation context

The CVE is not listed as KEV in the provided bundle, and no cited source states active exploitation. The described impact is remote unauthenticated denial of service through crafted HTTP traffic, with no public evidence here of code execution or persistence.

Researcher notes

The source data is sparse: no CVSS vector, CWE, exploit maturity, or interface exposure details are provided. Avoid assuming compromise beyond denial of service. Validation should focus on model and firmware matching, then vendor firmware confirmation.

Mitigation direction

  • Inventory listed ASUS router and ZenWiFi models.
  • Upgrade affected devices to the fixed firmware version or later.
  • For RT-AX68U, verify firmware is 3.0.0.4.386.45911 or later.
  • For other listed models, verify firmware is 3.0.0.4.386.45898 or later.
  • Check ASUS support pages for current model-specific guidance.

Validation and detection

  • Confirm exact router model and hardware variant.
  • Record current firmware version from device administration inventory.
  • Compare firmware against the fixed version named for that model.
  • Review ASUS support pages for the latest available firmware.
  • Monitor affected devices for unexpected web-interface crashes or reboots.
Prepared
Confidence
medium
Sources
9

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

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CVE-2021-41436 mapping review

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Vulnerability profileCVE Program record
Severity
Unknown
CVSS
Not scored
Known Exploited
No
Published
Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

0CVSS vectors
3Timeline events
1ADP providers
8Source links

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  2. CVE publishedCVE Program

    The CVE record was published.

  3. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

ADP provider summaries

CVECVE Program Container

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
n/an/an/aListed
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.