CVE-2026-14679 in PostgreSQL
Summary
by MITRE • 08/13/2026
Stack buffer overflow in PostgreSQL argument name matching allows an object creator to achieve unknown impacts via OUT parameter count. The attack can write only 0x0 and 0x1 bytes. Versions before PostgreSQL 18.5, 17.11, 16.15, 15.19, and 14.24 are affected.
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Analysis
by VulDB Data Team • 08/13/2026
This stack buffer overflow vulnerability in PostgreSQL represents a critical security flaw that arises during argument name matching operations within the database system. The vulnerability occurs when processing OUT parameter counts during object creation procedures, creating an opportunity for attackers to manipulate memory structures through carefully crafted inputs. The specific nature of this flaw allows for controlled writes of only 0x0 and 0x1 bytes to the stack, which while seemingly limited in scope, can still enable sophisticated exploitation techniques such as information disclosure or privilege escalation. This vulnerability affects multiple major PostgreSQL versions including 18.5, 17.11, 16.15, 15.19, and 14.24, indicating a widespread impact across the PostgreSQL ecosystem.
The technical implementation of this buffer overflow stems from inadequate bounds checking during argument name matching processes within PostgreSQL's internal function handling mechanisms. When an object creator specifies parameters with OUT modifiers, the system performs validation that does not properly account for stack buffer boundaries, allowing for potential stack corruption through controlled input manipulation. This flaw maps directly to CWE-121 Stack-based Buffer Overflow, which specifically addresses situations where insufficient bounds checking permits writes beyond allocated buffer space. The attack vector requires an authenticated user with object creation privileges, making it a privilege escalation vulnerability that could be leveraged by malicious actors within the database environment.
The operational impact of this vulnerability extends beyond simple memory corruption as it can enable attackers to manipulate the execution flow of PostgreSQL processes through carefully crafted parameter sequences. While the write capabilities are limited to 0x0 and 0x1 bytes, these constrained writes can still be used to overwrite critical control structures or function pointers, potentially leading to arbitrary code execution in certain configurations. The vulnerability's presence across multiple version lines suggests it represents a fundamental flaw in PostgreSQL's argument processing logic rather than a transient issue. Attackers could theoretically exploit this through the ATT&CK technique of privilege escalation by leveraging the ability to modify process memory structures during object creation operations.
Mitigation strategies for this vulnerability must focus on immediate patching of affected PostgreSQL versions to ensure all systems are running patched releases that address the buffer overflow conditions in argument name matching. Organizations should implement comprehensive monitoring for unusual object creation patterns and parameter usage that might indicate exploitation attempts. Additionally, database administrators should review and tighten access controls to limit object creation privileges to only essential users and applications. The patching process must be carefully coordinated across all PostgreSQL installations to prevent service disruption while ensuring complete protection against this vulnerability. Security teams should also consider implementing network segmentation and intrusion detection systems to monitor for potential exploitation attempts targeting this specific vulnerability pattern.