CVE-2026-6477 (GCVE-0-2026-6477)

Vulnerability from cvelistv5 – Published: 2026-05-14 13:00 – Updated: 2026-05-15 03:56
VLAI
Title
PostgreSQL libpq lo_* functions let server superuser overwrite client stack memory
Summary
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
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator (v2.0.3)
CWE
  • CWE-242 - Use of Inherently Dangerous Function
Assigner
References
Impacted products
Vendor Product Version
n/a PostgreSQL Affected: 18 , < 18.4 (rpm)
Affected: 17 , < 17.10 (rpm)
Affected: 16 , < 16.14 (rpm)
Affected: 15 , < 15.18 (rpm)
Affected: 0 , < 14.23 (rpm)
Credits
The PostgreSQL project thanks Yu Kunpeng and Martin Heistermann for reporting this problem.
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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