CVE-2026-43951 (GCVE-0-2026-43951)

Vulnerability from cvelistv5 – Published: 2026-06-08 15:16 – Updated: 2026-06-08 22:32
VLAI
Title
Apache HTTP Server: OOB Read in `merge_response_headers` can cause crash
Summary
Out-of-bounds Read vulnerability in Apache HTTP Server with mod_headers and mod_mime and multiple response languages. This issue affects Apache HTTP Server: from 2.4.0 through 2.4.67.
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-08 18:13 UTC
CWE
Impacted products
Vendor Product Version CPE status
Apache Software Foundation Apache HTTP Server Affected: 2.4.0 , ≤ 2.4.67 (semver)
guessed Create a notification for this product.
Show details on NVD website

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "NETWORK",
              "availabilityImpact": "NONE",
              "baseScore": 6.5,
              "baseSeverity": "MEDIUM",
              "confidentialityImpact": "LOW",
              "integrityImpact": "LOW",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2026-43951",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-08T18:13:37.250801Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-06-08T18:14:03.963Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      },
      {
        "providerMetadata": {
          "dateUpdated": "2026-06-08T22:32:28.584Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "url": "http://www.openwall.com/lists/oss-security/2026/06/08/10"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Apache HTTP Server",
          "vendor": "Apache Software Foundation",
          "versions": [
            {
              "lessThanOrEqual": "2.4.67",
              "status": "affected",
              "version": "2.4.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Zhenpeng (Leo) Lin at depthfirst"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "\u003cp\u003eOut-of-bounds Read vulnerability in Apache HTTP Server with mod_headers and mod_mime and multiple response languages.\u003c/p\u003e\u003cp\u003eThis issue affects Apache HTTP Server: from 2.4.0 through 2.4.67."
            }
          ],
          "value": "Out-of-bounds Read vulnerability in Apache HTTP Server with mod_headers and mod_mime and multiple response languages.\n\nThis issue affects Apache HTTP Server: from 2.4.0 through 2.4.67."
        }
      ],
      "metrics": [
        {
          "other": {
            "content": {
              "text": "moderate"
            },
            "type": "Textual description of severity"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-125",
              "description": "CWE-125 Out-of-bounds Read",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-06-08T15:16:14.594Z",
        "orgId": "f0158376-9dc2-43b6-827c-5f631a4d8d09",
        "shortName": "apache"
      },
      "references": [
        {
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://httpd.apache.org/security/vulnerabilities_24.html"
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "timeline": [
        {
          "lang": "en",
          "time": "2026-04-27T12:00:00.000Z",
          "value": "reported"
        },
        {
          "lang": "en",
          "time": "2026-06-05T12:00:00.000Z",
          "value": "fixed in 2.4.x by r1935006"
        },
        {
          "lang": "eng",
          "time": "2026-06-08T12:00:00.000Z",
          "value": "2.4.68 released"
        }
      ],
      "title": "Apache HTTP Server: OOB Read in `merge_response_headers` can cause crash",
      "x_generator": {
        "engine": "Vulnogram 0.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "f0158376-9dc2-43b6-827c-5f631a4d8d09",
    "assignerShortName": "apache",
    "cveId": "CVE-2026-43951",
    "datePublished": "2026-06-08T15:16:14.594Z",
    "dateReserved": "2026-05-04T17:15:44.253Z",
    "dateUpdated": "2026-06-08T22:32:28.584Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-43951",
      "date": "2026-09-21",
      "epss": "0.00545",
      "percentile": "0.4442"
    },
    "microsoft_vex": {
      "current_release_date": "2026-06-23T14:45:32.000Z",
      "cve": "CVE-2026-43951",
      "id": "msrc_CVE-2026-43951",
      "initial_release_date": "2026-06-02T00:00:00.000Z",
      "product_status:fixed": "1",
      "product_status:known_affected": "1",
      "source": "Microsoft CSAF VEX",
      "status": "final",
      "title": "Apache HTTP Server: OOB Read in `merge_response_headers` can cause crash",
      "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-43951.json",
      "version": "2"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Apache HTTP Server",
                "vendor": "Apache Software Foundation",
                "versions": [
                  {
                    "lessThanOrEqual": "2.4.67",
                    "status": "affected",
                    "version": "2.4.0",
                    "versionType": "semver"
                  }
                ]
              }
            ],
            "source": "security@apache.org"
          }
        ],
        "configurations": [
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "2A852E16-58B1-425F-98A7-E617B3DABC49",
                    "versionEndIncluding": "2.4.67",
                    "versionStartIncluding": "2.4.0",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "Out-of-bounds Read vulnerability in Apache HTTP Server with mod_headers and mod_mime and multiple response languages.\n\nThis issue affects Apache HTTP Server: from 2.4.0 through 2.4.67."
          },
          {
            "lang": "es",
            "value": "Vulnerabilidad de lectura fuera de l\u00edmites en Servidor HTTP Apache con mod_headers y mod_mime y m\u00faltiples idiomas de respuesta.\n\nEste problema afecta a Servidor HTTP Apache: desde 2.4.0 hasta 2.4.67."
          }
        ],
        "id": "CVE-2026-43951",
        "lastModified": "2026-07-23T07:10:00.113",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "NONE",
                "baseScore": 6.5,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "LOW",
                "integrityImpact": "LOW",
                "privilegesRequired": "NONE",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
                "version": "3.1"
              },
              "exploitabilityScore": 3.9,
              "impactScore": 2.5,
              "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "type": "Secondary"
            }
          ],
          "ssvcV203": [
            {
              "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "ssvcData": {
                "id": "CVE-2026-43951",
                "options": [
                  {
                    "exploitation": "none"
                  },
                  {
                    "automatable": "yes"
                  },
                  {
                    "technicalImpact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-08T18:13:37.250801Z",
                "version": "2.0.3"
              }
            }
          ]
        },
        "published": "2026-06-08T16:16:40.087",
        "references": [
          {
            "source": "security@apache.org",
            "tags": [
              "Vendor Advisory"
            ],
            "url": "https://httpd.apache.org/security/vulnerabilities_24.html"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Mailing List",
              "Third Party Advisory"
            ],
            "url": "http://www.openwall.com/lists/oss-security/2026/06/08/10"
          }
        ],
        "sourceIdentifier": "security@apache.org",
        "vulnStatus": "Analyzed",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-125"
              }
            ],
            "source": "security@apache.org",
            "type": "Secondary"
          }
        ]
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-09-18T17:44:36+00:00",
      "cve": "CVE-2026-43951",
      "id": "CVE-2026-43951",
      "initial_release_date": "2026-06-08T15:16:14.594000+00:00",
      "product_status:fixed": "403",
      "product_status:known_affected": "15",
      "product_status:known_not_affected": "172",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "httpd: Apache HTTP Server: Out-of-bounds Read in mod_headers and mod_mime",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-43951.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-09-11T01:16:42Z",
      "cve": "CVE-2026-43951",
      "id": "CVE-2026-43951",
      "initial_release_date": "2026-06-10T02:27:21Z",
      "product_status:known_affected": "490",
      "product_status:recommended": "201",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-43951",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-43951.json",
      "version": "10"
    },
    "vulnrichment": {
      "containers": {
        "adp": [
          {
            "providerMetadata": {
              "dateUpdated": "2026-06-08T22:32:28.584Z",
              "orgId": "af854a3a-2127-422b-91ae-364da2661108",
              "shortName": "CVE"
            },
            "references": [
              {
                "url": "http://www.openwall.com/lists/oss-security/2026/06/08/10"
              }
            ],
            "title": "CVE Program Container"
          },
          {
            "metrics": [
              {
                "cvssV3_1": {
                  "attackComplexity": "LOW",
                  "attackVector": "NETWORK",
                  "availabilityImpact": "NONE",
                  "baseScore": 6.5,
                  "baseSeverity": "MEDIUM",
                  "confidentialityImpact": "LOW",
                  "integrityImpact": "LOW",
                  "privilegesRequired": "NONE",
                  "scope": "UNCHANGED",
                  "userInteraction": "NONE",
                  "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
                  "version": "3.1"
                }
              },
              {
                "other": {
                  "content": {
                    "id": "CVE-2026-43951",
                    "options": [
                      {
                        "Exploitation": "none"
                      },
                      {
                        "Automatable": "yes"
                      },
                      {
                        "Technical Impact": "partial"
                      }
                    ],
                    "role": "CISA Coordinator",
                    "timestamp": "2026-06-08T18:13:37.250801Z",
                    "version": "2.0.3"
                  },
                  "type": "ssvc"
                }
              }
            ],
            "providerMetadata": {
              "dateUpdated": "2026-06-08T18:13:58.958Z",
              "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "shortName": "CISA-ADP"
            },
            "title": "CISA ADP Vulnrichment"
          }
        ],
        "cna": {
          "affected": [
            {
              "defaultStatus": "unaffected",
              "product": "Apache HTTP Server",
              "vendor": "Apache Software Foundation",
              "versions": [
                {
                  "lessThanOrEqual": "2.4.67",
                  "status": "affected",
                  "version": "2.4.0",
                  "versionType": "semver"
                }
              ]
            }
          ],
          "credits": [
            {
              "lang": "en",
              "type": "finder",
              "value": "Zhenpeng (Leo) Lin at depthfirst"
            }
          ],
          "descriptions": [
            {
              "lang": "en",
              "supportingMedia": [
                {
                  "base64": false,
                  "type": "text/html",
                  "value": "\u003cp\u003eOut-of-bounds Read vulnerability in Apache HTTP Server with mod_headers and mod_mime and multiple response languages.\u003c/p\u003e\u003cp\u003eThis issue affects Apache HTTP Server: from 2.4.0 through 2.4.67."
                }
              ],
              "value": "Out-of-bounds Read vulnerability in Apache HTTP Server with mod_headers and mod_mime and multiple response languages.\n\nThis issue affects Apache HTTP Server: from 2.4.0 through 2.4.67."
            }
          ],
          "metrics": [
            {
              "other": {
                "content": {
                  "text": "moderate"
                },
                "type": "Textual description of severity"
              }
            }
          ],
          "problemTypes": [
            {
              "descriptions": [
                {
                  "cweId": "CWE-125",
                  "description": "CWE-125 Out-of-bounds Read",
                  "lang": "en",
                  "type": "CWE"
                }
              ]
            }
          ],
          "providerMetadata": {
            "dateUpdated": "2026-06-08T15:16:14.594Z",
            "orgId": "f0158376-9dc2-43b6-827c-5f631a4d8d09",
            "shortName": "apache"
          },
          "references": [
            {
              "tags": [
                "vendor-advisory"
              ],
              "url": "https://httpd.apache.org/security/vulnerabilities_24.html"
            }
          ],
          "source": {
            "discovery": "UNKNOWN"
          },
          "timeline": [
            {
              "lang": "en",
              "time": "2026-04-27T12:00:00.000Z",
              "value": "reported"
            },
            {
              "lang": "en",
              "time": "2026-06-05T12:00:00.000Z",
              "value": "fixed in 2.4.x by r1935006"
            },
            {
              "lang": "eng",
              "time": "2026-06-08T12:00:00.000Z",
              "value": "2.4.68 released"
            }
          ],
          "title": "Apache HTTP Server: OOB Read in `merge_response_headers` can cause crash",
          "x_generator": {
            "engine": "Vulnogram 0.2.0"
          }
        }
      },
      "cveMetadata": {
        "assignerOrgId": "f0158376-9dc2-43b6-827c-5f631a4d8d09",
        "assignerShortName": "apache",
        "cveId": "CVE-2026-43951",
        "datePublished": "2026-06-08T15:16:14.594Z",
        "dateReserved": "2026-05-04T17:15:44.253Z",
        "dateUpdated": "2026-06-08T22:32:28.584Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.


Loading…

Loading…

Loading…

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.

Loading…

Detection rules are retrieved from Rulezet.

Loading…

Loading…

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.


Loading…