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{"bugzilla": {"description": "postgresql: PostgreSQL libpq: Buffer overflow allows server superuser to overwrite client stack memory", "id": "2477442", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2477442"}, "csaw": false, "cvss3": {"cvss3_base_score": "8.4", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:H", "status": "draft"}, "cwe": "CWE-120", "details": ["A flaw was found in PostgreSQL libpq. A server superuser can exploit a buffer overflow vulnerability in the PQfn function, which is used by client functions such as lo_export(), lo_read(), lo_lseek64(), and lo_tell64(). This allows the superuser to send an arbitrarily large response, overwriting the client's stack memory, specifically in tools like psql and pg_dump. This could lead to arbitrary code execution on the client system."], "mitigation": {"lang": "en:us", "value": "Only connect to trusted PostgreSQL servers. Avoid using psql or pg_dump against untrusted or potentially compromised database servers."}, "name": "CVE-2026-6477", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "postgresql16", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "postgresql18", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "postgresql", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Affected", "package_name": "postgresql", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "libpq", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "postgresql", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "postgresql-jdbc", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "postgresql", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "postgresql:15/postgresql", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "postgresql:16/postgresql", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "postgresql:18/postgresql", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Not affected", "package_name": "postgresql17", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "postgresql18", "product_name": "Red Hat Hardened Images"}], "public_date": "2026-05-14T13:00:12Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-6477\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-6477\nhttps://www.postgresql.org/support/security/CVE-2026-6477/"], "statement": "This IMPORTANT buffer overflow in PostgreSQL libpq allows a malicious server superuser to overwrite client stack memory via lo_* functions. Exploitation requires the victim to connect to a compromised or malicious server (UI:R). The scope is changed as the server attack affects the client system. Impact is high to confidentiality, integrity, and availability through potential client-side code execution. Affects versions before 18.4, 17.10, 16.14, 15.18, and 14.23.", "threat_severity": "Important"}

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