CVE-2026-84895 (GCVE-0-2026-84895)

Vulnerability from cvelistv5 – Published: 2026-09-28 20:44 – Updated: 2026-09-28 20:44
VLAI
Summary
In proxygen from v2026.04.06.00 until v2026.09.28.00, QuicWtSession::closeSession accesses its member fields after calling the base QuicWtSessionBase::closeSession method. The base method notifies the session handler, which may release the last reference to the session and destroy it.
Severity
No CVSS data available.
CWE
  • Use After Free (CWE-416)
Assigner
References
Impacted products
Vendor Product Version CPE status
Facebook proxygen Affected: v2026.04.06.00 , < v2026.09.28.00 (semver)
guessed Create a notification for this product.
Show details on NVD website
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          "product": "proxygen",
          "vendor": "Facebook",
          "versions": [
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              "status": "affected",
              "version": "v2026.04.06.00",
              "versionType": "semver"
            }
          ]
        }
      ],
      "dateAssigned": "2026-09-02T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "In proxygen from v2026.04.06.00 until v2026.09.28.00, QuicWtSession::closeSession accesses its member fields after calling the base QuicWtSessionBase::closeSession method. The base method notifies the session handler, which may release the last reference to the session and destroy it."
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "description": "Use After Free (CWE-416)",
              "lang": "en"
            }
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      "providerMetadata": {
        "dateUpdated": "2026-09-28T20:44:34.886Z",
        "orgId": "4fc57720-52fe-4431-a0fb-3d2c8747b827",
        "shortName": "Meta"
      },
      "references": [
        {
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://www.facebook.com/security/advisories/cve-2026-84895"
        },
        {
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/facebook/proxygen/commit/479eb5574195764e80e6cedebef669f6baa85083"
        }
      ]
    }
  },
  "cveMetadata": {
    "assignerOrgId": "4fc57720-52fe-4431-a0fb-3d2c8747b827",
    "assignerShortName": "Meta",
    "cveId": "CVE-2026-84895",
    "datePublished": "2026-09-28T20:44:34.886Z",
    "dateReserved": "2026-09-02T14:52:36.354Z",
    "dateUpdated": "2026-09-28T20:44:34.886Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
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      "cve": {
        "affected": [
          {
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                "product": "proxygen",
                "vendor": "Facebook",
                "versions": [
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                    "version": "v2026.04.06.00",
                    "versionType": "semver"
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            ],
            "source": "cve-assign@fb.com"
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        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In proxygen from v2026.04.06.00 until v2026.09.28.00, QuicWtSession::closeSession accesses its member fields after calling the base QuicWtSessionBase::closeSession method. The base method notifies the session handler, which may release the last reference to the session and destroy it."
          }
        ],
        "id": "CVE-2026-84895",
        "lastModified": "2026-09-28T21:17:19.130",
        "metrics": {},
        "published": "2026-09-28T21:17:19.027",
        "references": [
          {
            "source": "cve-assign@fb.com",
            "url": "https://github.com/facebook/proxygen/commit/479eb5574195764e80e6cedebef669f6baa85083"
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            "url": "https://www.facebook.com/security/advisories/cve-2026-84895"
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        ],
        "sourceIdentifier": "cve-assign@fb.com",
        "vulnStatus": "Deferred"
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    "redhat_vex": {
      "current_release_date": "2026-09-29T06:40:07+00:00",
      "cve": "CVE-2026-84895",
      "id": "CVE-2026-84895",
      "initial_release_date": "2026-09-28T20:44:34.886000+00:00",
      "product_status:known_not_affected": "1",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "proxygen: proxygen: Denial of Service via use-after-free during session closure",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-84895.json",
      "version": "3"
    }
  }
}



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