CVE-2026-6637: Stack-based Buffer Overflow in PostgreSQL
Stack buffer overflow in PostgreSQL module "refint" allows an unprivileged database user to execute arbitrary code as the operating system user running the database. A distinct attack is possible if the application declares a user-controlled column as a "refint" cascade primary key and facilitates user-controlled updates to that column. In that case, a SQL injection allows a primary key update value provider to execute arbitrary SQL as the database user performing the primary key update. Versions before PostgreSQL 18.4, 17.10, 16.14, 15.18, and 14.23 are affected.
AI Analysis
Technical Summary
This vulnerability involves a stack buffer overflow in the PostgreSQL "refint" module that can be exploited by an unprivileged database user to execute arbitrary code with the privileges of the OS user running the database. A separate attack vector exists where a user-controlled "refint" cascade primary key column combined with user-controlled updates can lead to SQL injection, allowing arbitrary SQL execution by the database user performing the update. The affected versions include all versions before PostgreSQL 18.4, 17.10, 16.14, 15.18, and 14.23. The CVSS v3.1 score is 8.8, indicating high severity with network attack vector, low attack complexity, requiring low privileges but no user interaction, and impacts on confidentiality, integrity, and availability.
Potential Impact
Successful exploitation can lead to arbitrary code execution at the operating system level with the privileges of the database process user, potentially compromising the host system. The SQL injection variant allows arbitrary SQL execution as the database user, which can lead to unauthorized data manipulation or disclosure. This poses a significant risk to database integrity, confidentiality, and availability.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict unprivileged database user permissions to minimize exposure. Avoid using user-controlled columns as "refint" cascade primary keys with user-controlled updates. Monitor vendor channels for patches and updates addressing this vulnerability.
CVE-2026-6637: Stack-based Buffer Overflow in PostgreSQL
Description
Stack buffer overflow in PostgreSQL module "refint" allows an unprivileged database user to execute arbitrary code as the operating system user running the database. A distinct attack is possible if the application declares a user-controlled column as a "refint" cascade primary key and facilitates user-controlled updates to that column. In that case, a SQL injection allows a primary key update value provider to execute arbitrary SQL as the database user performing the primary key update. Versions before PostgreSQL 18.4, 17.10, 16.14, 15.18, and 14.23 are affected.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves a stack buffer overflow in the PostgreSQL "refint" module that can be exploited by an unprivileged database user to execute arbitrary code with the privileges of the OS user running the database. A separate attack vector exists where a user-controlled "refint" cascade primary key column combined with user-controlled updates can lead to SQL injection, allowing arbitrary SQL execution by the database user performing the update. The affected versions include all versions before PostgreSQL 18.4, 17.10, 16.14, 15.18, and 14.23. The CVSS v3.1 score is 8.8, indicating high severity with network attack vector, low attack complexity, requiring low privileges but no user interaction, and impacts on confidentiality, integrity, and availability.
Potential Impact
Successful exploitation can lead to arbitrary code execution at the operating system level with the privileges of the database process user, potentially compromising the host system. The SQL injection variant allows arbitrary SQL execution as the database user, which can lead to unauthorized data manipulation or disclosure. This poses a significant risk to database integrity, confidentiality, and availability.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict unprivileged database user permissions to minimize exposure. Avoid using user-controlled columns as "refint" cascade primary keys with user-controlled updates. Monitor vendor channels for patches and updates addressing this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- PostgreSQL
- Date Reserved
- 2026-04-19T19:58:20.340Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a05cfeaec166c07b0e13e27
Added to database: 5/14/2026, 1:36:42 PM
Last enriched: 5/14/2026, 1:51:37 PM
Last updated: 5/14/2026, 4:15:59 PM
Views: 7
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