PostgreSQL up to 18.3 libpq lo_export/lo_read/lo_lseek64/lo_tell64 inherently dangerous function

CVSS Meta Temp Score
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CTI Interest Score
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7.4$0-$5k0.00

Summaryinfo

A vulnerability classified as critical was found in PostgreSQL up to 14.22/15.17/16.13/17.9/18.3. Impacted is the function lo_export/lo_read/lo_lseek64/lo_tell64 of the component libpq. Executing a manipulation can lead to use of inherently dangerous function. The identification of this vulnerability is CVE-2026-6477. The attack may be launched remotely. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability has been found in PostgreSQL up to 14.22/15.17/16.13/17.9/18.3 and classified as critical. This vulnerability affects the function lo_export/lo_read/lo_lseek64/lo_tell64 of the component libpq. The manipulation with an unknown input leads to a use of inherently dangerous function vulnerability. The CWE definition for the vulnerability is CWE-242. The product calls a function that can never be guaranteed to work safely. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is available at postgresql.org. This vulnerability was named CVE-2026-6477 since 04/17/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Successful exploitation requires user interaction by the victim. Technical details are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 315292 (SUSE SLES12 Security Update : postgresql18 (SUSE-SU-2026:1946-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 14.23, 15.18, 16.14, 17.10 or 18.4 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (315292) and CERT Bund (WID-SEC-2026-1544). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • RESF Rocky Linux
  • Open Source PostgreSQL
  • IBM QRadar SIEM

Productinfo

Type

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.6
VulDB Meta Temp Score: 7.4

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 8.8
CNA Vector (PostgreSQL): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Use of inherently dangerous function
CWE: CWE-242 / CWE-18 / CWE-17
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 315292
Nessus Name: SUSE SLES12 Security Update : postgresql18 (SUSE-SU-2026:1946-1)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: PostgreSQL 14.23/15.18/16.14/17.10/18.4

Timelineinfo

04/17/2026 CVE reserved
05/14/2026 +27 days Advisory disclosed
05/14/2026 +0 days VulDB entry created
06/25/2026 +42 days VulDB entry last update

Sourcesinfo

Product: postgresql.org

Advisory: postgresql.org
Status: Confirmed

CVE: CVE-2026-6477 (🔒)
GCVE (CVE): GCVE-0-2026-6477
GCVE (VulDB): GCVE-100-363874
CERT Bund: WID-SEC-2026-1544 - PostgreSQL: Mehrere Schwachstellen

Entryinfo

Created: 05/14/2026 15:49
Updated: 06/25/2026 15:45
Changes: 05/14/2026 15:49 (64), 05/16/2026 00:14 (7), 05/19/2026 15:19 (2), 05/28/2026 10:16 (1), 06/15/2026 15:33 (1), 06/25/2026 15:45 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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