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.
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Affected Vendors & Products
References
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| https://www.postgresql.org/support/security/CVE-2026-6477/ |
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History
Thu, 14 May 2026 16:30:00 +0000
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Thu, 14 May 2026 15:00:00 +0000
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Postgresql postgresql |
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Thu, 14 May 2026 13:30:00 +0000
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| Description | 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. | |
| Title | PostgreSQL libpq lo_* functions let server superuser overwrite client stack memory | |
| Weaknesses | CWE-242 | |
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cvssV3_1
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Status: PUBLISHED
Assigner: PostgreSQL
Published:
Updated: 2026-05-14T15:32:30.106Z
Reserved: 2026-04-17T00:44:19.965Z
Link: CVE-2026-6477
Updated: 2026-05-14T15:32:25.888Z
Status : Awaiting Analysis
Published: 2026-05-14T14:16:25.347
Modified: 2026-05-14T16:21:23.190
Link: CVE-2026-6477
No data.