CVE-2026-40435 (GCVE-0-2026-40435)
Vulnerability from cvelistv5
Published
2026-05-13 14:12
Modified
2026-05-13 16:17
Severity ?
5.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
6.9 (Medium) - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
CWE
  • CWE-420 - Unprotected Alternate Channel
Summary
When configured, IP-based access restrictions for httpd do not cover all endpoints, which may allow connections from blocked addresses.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
References
Impacted products
Vendor Product Version
F5 BIG-IP Patch: 21.0.0   < *
Version: 17.5.0   < 17.5.1.4
Version: 17.1.0   < 17.1.3.1
Version: 16.1.0   < *
 Create a notification for this product.
Show details on NVD website

To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-40435",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-05-13T16:00:56.205672Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-05-13T16:17:55.858Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unknown",
          "modules": [
            "All Modules"
          ],
          "product": "BIG-IP",
          "vendor": "F5",
          "versions": [
            {
              "lessThan": "*",
              "status": "unaffected",
              "version": "21.0.0",
              "versionType": "custom"
            },
            {
              "lessThan": "17.5.1.4",
              "status": "affected",
              "version": "17.5.0",
              "versionType": "custom"
            },
            {
              "lessThan": "17.1.3.1",
              "status": "affected",
              "version": "17.1.0",
              "versionType": "custom"
            },
            {
              "lessThan": "*",
              "status": "affected",
              "version": "16.1.0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "F5"
        }
      ],
      "datePublic": "2026-05-13T14:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "\u003cspan style=\"background-color: rgb(255, 255, 255);\"\u003e\n\n\u003cspan style=\"background-color: rgb(255, 255, 255);\"\u003eWhen configured, IP-based access restrictions for \u003c/span\u003e\u003cstrong\u003ehttpd\u003c/strong\u003e\u003cspan style=\"background-color: rgb(255, 255, 255);\"\u003e\u0026nbsp;do not cover all endpoints, which may allow connections from blocked addresses.\u003c/span\u003e\u0026nbsp;\u0026nbsp;\u003c/span\u003eNote: Software versions which have reached End of Technical Support (EoTS) are not evaluated."
            }
          ],
          "value": "When configured, IP-based access restrictions for httpd\u00a0do not cover all endpoints, which may allow connections from blocked addresses.\u00a0\u00a0Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 5.3,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "LOW",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        },
        {
          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 6.9,
            "baseSeverity": "MEDIUM",
            "privilegesRequired": "NONE",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "LOW",
            "vulnIntegrityImpact": "NONE",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-420",
              "description": "CWE-420: Unprotected Alternate Channel",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-13T14:12:27.268Z",
        "orgId": "9dacffd4-cb11-413f-8451-fbbfd4ddc0ab",
        "shortName": "f5"
      },
      "references": [
        {
          "tags": [
            "vendor-advisory",
            "patch"
          ],
          "url": "https://my.f5.com/manage/s/article/K000156604"
        }
      ],
      "source": {
        "discovery": "INTERNAL"
      },
      "title": "BIG-IP httpd access control vulnerability",
      "x_generator": {
        "engine": "F5 SIRTBot v1.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "9dacffd4-cb11-413f-8451-fbbfd4ddc0ab",
    "assignerShortName": "f5",
    "cveId": "CVE-2026-40435",
    "datePublished": "2026-05-13T14:12:27.268Z",
    "dateReserved": "2026-04-30T23:02:33.887Z",
    "dateUpdated": "2026-05-13T16:17:55.858Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.