Critical

ProxySQL pre-auth heap overflow in MySQL and PostgreSQL first-packet handling

Type: advisorySources: OSV

ProxySQL is a proxy for MySQL and its forks, as well as PostgreSQL. Versions 2.0.18 through 3.0.8 have a pre-authentication heap memory corruption vulnerability in the MySQL and PostgreSQL protocol first-read paths. A remote unauthenticated client can declare an oversized first packet length, and ProxySQL passes that attacker-controlled length directly to `recv()` while writing into a fixed 32 KB input queue. Version 3.0.9 patches the issue.

Products: Not specified
Affected versions: Not specified
Fixed versions: Not specified
CVEs: CVE-2026-48773
Confirmed fixed CVEs: Not specified
Updated in this feed: 2 Nov 2026, 20:11 UTC · Revision 1

Source evidence

ProxySQL pre-auth heap overflow in MySQL and PostgreSQL first-packet handling

core-osv · Original source

Published 19 Jun 2026, 19:27 UTC

osv:CVE-2026-48773

Complete source record

{
  "id": "577f680f09543f5e91bb524331c044f0b7bb2dfa01e61916142dc312ab472c10",
  "url": "https://osv.dev/vulnerability/CVE-2026-48773",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "ProxySQL pre-auth heap overflow in MySQL and PostgreSQL first-packet handling",
    "summary": "ProxySQL is a proxy for MySQL and its forks, as well as PostgreSQL. Versions 2.0.18 through 3.0.8 have a pre-authentication heap memory corruption vulnerability in the MySQL and PostgreSQL protocol first-read paths. A remote unauthenticated client can declare an oversized first packet length, and ProxySQL passes that attacker-controlled length directly to `recv()` while writing into a fixed 32 KB input queue. Version 3.0.9 patches the issue.",
    "evidence": "osv:CVE-2026-48773",
    "products": [],
    "severity": "critical",
    "structured": {
      "id": "CVE-2026-48773",
      "aliases": [
        "BIT-proxysql-2026-48773",
        "CVE-2026-48773",
        "GHSA-58ww-865x-grpr"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/sysown/proxysql",
              "type": "GIT",
              "events": [
                {
                  "introduced": "1c2b7e410551affac4e26d1b67646a2e51bd43da"
                },
                {
                  "fixed": "7ddb3dc015d1440e8a0fb0bbafa2df9aaaa2669d"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "2.0.18"
                      },
                      {
                        "fixed": "3.0.9"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  },
                  {
                    "range": [
                      {
                        "fixed": "7ddb3dc015d1440e8a0fb0bbafa2df9aaaa2669d"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "v3.0.9"
                  },
                  {
                    "cpe": "cpe:2.3:a:proxysql:proxysql:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "2.0.18"
                      },
                      {
                        "fixed": "3.0.9"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v4.0.8",
            "v3.1.8",
            "v3.0.8",
            "3.0.9",
            "3.0.8",
            "v4.0.7",
            "v3.1.7",
            "v3.0.7",
            "v4.0.6",
            "v3.1.6",
            "v3.0.6",
            "3.0.6",
            "v3.0.5",
            "3.0.5",
            "v3.0.4",
            "3.0.4",
            "v3.0.3",
            "v3.0.2",
            "3.0.3",
            "3.0.2",
            "v3.0.1",
            "v3.0.0-alpha",
            "v2.5.5",
            "v2.5.4",
            "2.6.0",
            "2.5.4",
            "v2.5.3",
            "2.5.3",
            "v2.5.2",
            "2.5.2",
            "v2.5.1",
            "v2.5.0",
            "2.5.1",
            "v2.4.7",
            "2.5.0",
            "2.4.7",
            "v2.4.6",
            "2.4.6",
            "v2.4.5",
            "2.4.5",
            "v2.4.4",
            "2.4.4",
            "v2.4.3",
            "2.4.3",
            "v2.4.2",
            "2.4.2",
            "v2.4.1",
            "2.4.1",
            "v2.4.0",
            "2.4.0",
            "v2.2.0",
            "2.2.0",
            "v2.1.1",
            "v2.0.18"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-48773.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:23.030981454Z",
      "provider": "osv",
      "references": [
        "https://github.com/sysown/proxysql/releases/tag/v3.0.9",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/48xxx/CVE-2026-48773.json",
        "https://github.com/sysown/proxysql/security/advisories/GHSA-58ww-865x-grpr",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-48773"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-787"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/48xxx/CVE-2026-48773.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-48773",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 489664,
  "published_at": "2026-06-19T19:27:12.183+00:00"
}