Vulnerability-Lookup

FKIE_CVE-2021-31755

Vulnerability from fkie_nvd - Published: 2021-05-07 23:15 - Updated: 2026-06-17 03:52

Severity

9.8 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Summary

An issue was discovered on Tenda AC11 devices with firmware through 02.03.01.104_CN. A stack buffer overflow vulnerability in /goform/setmac allows attackers to execute arbitrary code on the system via a crafted post request.

References

URL	Tags
cve@mitre.org	https://github.com/Yu3H0/IoT_CVE/tree/main/Tenda/CVE_3	Broken Link, Exploit, Issue Tracking, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108	https://github.com/Yu3H0/IoT_CVE/tree/main/Tenda/CVE_3	Broken Link, Exploit, Issue Tracking, Third Party Advisory
134c704f-9b21-4f2e-91b3-4a467353bcc0	https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-31755	US Government Resource

Impacted products

	Vendor	Product	Version
	tenda	ac11_firmware	*
	tenda	ac11	-

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "n/a",
          "vendor": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "n/a"
            }
          ]
        }
      ],
      "source": "cve@mitre.org"
    }
  ],
  "cisaActionDue": "2021-11-17",
  "cisaExploitAdd": "2021-11-03",
  "cisaRequiredAction": "Apply updates per vendor instructions.",
  "cisaVulnerabilityName": "Tenda AC11 Router Stack Buffer Overflow Vulnerability",
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:tenda:ac11_firmware:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "08B4F9BE-9D0D-4297-A0EE-2B8D4853DD0E",
              "versionEndIncluding": "02.03.01.104_cn",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        },
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:h:tenda:ac11:-:*:*:*:*:*:*:*",
              "matchCriteriaId": "8850E87F-3B1D-4D24-8F22-B358B27EE582",
              "vulnerable": false
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ],
      "operator": "AND"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "An issue was discovered on Tenda AC11 devices with firmware through 02.03.01.104_CN. A stack buffer overflow vulnerability in /goform/setmac allows attackers to execute arbitrary code on the system via a crafted post request."
    },
    {
      "lang": "es",
      "value": "Se detect\u00f3 un problema en los dispositivos Tenda AC11 con firmware hasta 02.03.01.104_CN. Una vulnerabilidad de desbordamiento del b\u00fafer de la pila en /goform/setmac permite a los atacantes ejecutar c\u00f3digo arbitrario en el sistema a trav\u00e9s de una solicitud de correo manipulada"
    }
  ],
  "id": "CVE-2021-31755",
  "lastModified": "2026-06-17T03:52:12.150",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "HIGH",
        "cvssData": {
          "accessComplexity": "LOW",
          "accessVector": "NETWORK",
          "authentication": "NONE",
          "availabilityImpact": "COMPLETE",
          "baseScore": 10.0,
          "confidentialityImpact": "COMPLETE",
          "integrityImpact": "COMPLETE",
          "vectorString": "AV:N/AC:L/Au:N/C:C/I:C/A:C",
          "version": "2.0"
        },
        "exploitabilityScore": 10.0,
        "impactScore": 10.0,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 9.8,
          "baseSeverity": "CRITICAL",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 5.9,
        "source": "nvd@nist.gov",
        "type": "Primary"
      },
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 9.8,
          "baseSeverity": "CRITICAL",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 5.9,
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2021-31755",
          "options": [
            {
              "exploitation": "active"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2025-02-04T19:44:13.561933Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2021-05-07T23:15:07.047",
  "references": [
    {
      "source": "cve@mitre.org",
      "tags": [
        "Broken Link",
        "Exploit",
        "Issue Tracking",
        "Third Party Advisory"
      ],
      "url": "https://github.com/Yu3H0/IoT_CVE/tree/main/Tenda/CVE_3"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Broken Link",
        "Exploit",
        "Issue Tracking",
        "Third Party Advisory"
      ],
      "url": "https://github.com/Yu3H0/IoT_CVE/tree/main/Tenda/CVE_3"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "tags": [
        "US Government Resource"
      ],
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-31755"
    }
  ],
  "sourceIdentifier": "cve@mitre.org",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-787"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    },
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-787"
        }
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary"
    }
  ]
}

CVE-2021-31755 (GCVE-0-2021-31755)

Vulnerability from cvelistv5 – Published: 2021-05-07 22:01 – Updated: 2025-10-21 23:25

Summary

Severity

9.8 (Critical)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

SSVC

Exploitation: active Automatable: yes Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2025-02-04 19:44 UTC

CWE

n/a
CWE-787 - Out-of-bounds Write

Assigner

mitre mitre root

References

2 references

URL	Tags
https://github.com/Yu3H0/IoT_CVE/tree/main/Tenda/CVE_3	x_refsource_MISC
https://www.cisa.gov/known-exploited-vulnerabilit…	government-resource

Date Public

2021-04-24 00:00

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-03T23:03:33.780Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "tags": [
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              "x_transferred"
            ],
            "url": "https://github.com/Yu3H0/IoT_CVE/tree/main/Tenda/CVE_3"
          }
        ],
        "title": "CVE Program Container"
      },
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "NETWORK",
              "availabilityImpact": "HIGH",
              "baseScore": 9.8,
              "baseSeverity": "CRITICAL",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "HIGH",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2021-31755",
                "options": [
                  {
                    "Exploitation": "active"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-02-04T19:44:13.561933Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          },
          {
            "other": {
              "content": {
                "dateAdded": "2021-11-03",
                "reference": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-31755"
              },
              "type": "kev"
            }
          }
        ],
        "problemTypes": [
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        "providerMetadata": {
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            "time": "2021-11-03T00:00:00.000Z",
            "value": "CVE-2021-31755 added to CISA KEV"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
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                "product": {
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}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.