CVE-2026-110249 (GCVE-0-2026-110249)

Vulnerability from cvelistv5 – Published: 2026-10-13 18:08 – Updated: 2026-10-13 18:16
VLAI
Title
Denial-of-service in the Exchange email component
Summary
A malicious, compromised, or MITM-controlled Exchange server can return a single well-formed SOAP response containing an element with enough attributes to keep Thunderbird's main thread CPU-bound for seconds to hours. This vulnerability was fixed in Thunderbird 158 and Thunderbird 153.5.
Severity
No CVSS data available.
Assigner
mozilla CNA under the mitre root
CNA scorecard E 38/100 over 546 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Mozilla Thunderbird Unaffected: 153.5 , ≤ 153.* (rpm)
Unaffected: 158 , ≤ * (rpm)
guessed Create a notification for this product.
Credits
SuyZ
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "product": "Thunderbird",
          "vendor": "Mozilla",
          "versions": [
            {
              "lessThanOrEqual": "153.*",
              "status": "unaffected",
              "version": "153.5",
              "versionType": "rpm"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "158",
              "versionType": "rpm"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "SuyZ"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "A malicious, compromised, or MITM-controlled Exchange server can return a single well-formed SOAP response containing an element with enough attributes to keep Thunderbird\u0027s main thread CPU-bound for seconds to hours. This vulnerability was fixed in Thunderbird 158 and Thunderbird 153.5."
            }
          ],
          "value": "A malicious, compromised, or MITM-controlled Exchange server can return a single well-formed SOAP response containing an element with enough attributes to keep Thunderbird\u0027s main thread CPU-bound for seconds to hours. This vulnerability was fixed in Thunderbird 158 and Thunderbird 153.5."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-13T18:16:44.469Z",
        "orgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe",
        "shortName": "mozilla"
      },
      "references": [
        {
          "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2077826"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-109/"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-110/"
        }
      ],
      "title": "Denial-of-service in the Exchange email component"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe",
    "assignerShortName": "mozilla",
    "cveId": "CVE-2026-110249",
    "datePublished": "2026-10-13T18:08:38.179Z",
    "dateReserved": "2026-10-13T18:08:37.893Z",
    "dateUpdated": "2026-10-13T18:16:44.469Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-110249",
      "date": "2026-10-16",
      "epss": "0.00171",
      "percentile": "0.06098"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "product": "Thunderbird",
                "vendor": "Mozilla",
                "versions": [
                  {
                    "lessThanOrEqual": "153.*",
                    "status": "unaffected",
                    "version": "153.5",
                    "versionType": "rpm"
                  },
                  {
                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "158",
                    "versionType": "rpm"
                  }
                ]
              }
            ],
            "source": "security@mozilla.org"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "A malicious, compromised, or MITM-controlled Exchange server can return a single well-formed SOAP response containing an element with enough attributes to keep Thunderbird\u0027s main thread CPU-bound for seconds to hours. This vulnerability was fixed in Thunderbird 158 and Thunderbird 153.5."
          }
        ],
        "id": "CVE-2026-110249",
        "lastModified": "2026-10-13T19:30:29.797",
        "metrics": {},
        "published": "2026-10-13T19:18:49.590",
        "references": [
          {
            "source": "security@mozilla.org",
            "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2077826"
          },
          {
            "source": "security@mozilla.org",
            "url": "https://www.mozilla.org/security/advisories/mfsa2026-109/"
          },
          {
            "source": "security@mozilla.org",
            "url": "https://www.mozilla.org/security/advisories/mfsa2026-110/"
          }
        ],
        "sourceIdentifier": "security@mozilla.org",
        "vulnStatus": "Awaiting Analysis"
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-10-13T20:49:54+00:00",
      "cve": "CVE-2026-110249",
      "id": "CVE-2026-110249",
      "initial_release_date": "2026-10-13T18:08:38.179000+00:00",
      "product_status:known_affected": "6",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "thunderbird: thunderbird: Denial of Service via excessive attributes in SOAP response",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-110249.json",
      "version": "3"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

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.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

JSON

Loading timeline…




    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.