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GHSA-JM5F-GPFQ-Q9H3

Vulnerability from github – Published: 2026-05-14 15:31 – Updated: 2026-08-25 15:32
VLAI
Details

Use of inherently dangerous function PQfn(..., result_is_int=0, ...) in PostgreSQL libpq lo_export(), lo_read(), lo_lseek64(), and lo_tell64() functions allows the server superuser to overwrite a client stack buffer with an arbitrarily-large response. Like gets(), PQfn(..., result_is_int=0, ...) stores arbitrary-length, server-determined data into a buffer of unspecified size. Because both the \lo_export command in psql and pg_dump call lo_read(), the server superuser can overwrite pg_dump or psql stack memory. Versions before PostgreSQL 18.4, 17.10, 16.14, 15.18, and 14.23 are affected.

Severity
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
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{
  "affected": [],
  "aliases": [
    "CVE-2026-6477"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-120",
      "CWE-242"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-14T14:16:25Z",
    "severity": "HIGH"
  },
  "details": "Use of inherently dangerous function PQfn(..., result_is_int=0, ...) in PostgreSQL libpq lo_export(), lo_read(), lo_lseek64(), and lo_tell64() functions allows the server superuser to overwrite a client stack buffer with an arbitrarily-large response.  Like gets(), PQfn(..., result_is_int=0, ...) stores arbitrary-length, server-determined data into a buffer of unspecified size.  Because both the \\lo_export command in psql and pg_dump call lo_read(), the server superuser can overwrite pg_dump or psql stack memory.  Versions before PostgreSQL 18.4, 17.10, 16.14, 15.18, and 14.23 are affected.",
  "id": "GHSA-jm5f-gpfq-q9h3",
  "modified": "2026-08-25T15:32:23Z",
  "published": "2026-05-14T15:31:58Z",
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}



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