CVE-2026-119379 in SQLite
Summary
by MITRE • 10/30/2026
SQLite before 3.54.0 built with the session extension contains a heap buffer overflow vulnerability in sqlite3changeset_apply() that allows attackers to corrupt heap memory by supplying crafted changesets. Attackers can repeat a table name in a second changeset block with a larger column count, causing sessionUpdateFind() to memset past the undersized aUpdateMask allocation.
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Analysis
by VulDB Data Team • 10/30/2026
The vulnerability identified in SQLite versions prior to 3.54.0 represents a critical heap-based buffer overflow within the session extension functionality. This specific flaw is located in the sqlite3changeset_apply function, which is responsible for applying changesets to an existing database schema and data state. The root cause of this issue stems from improper bounds checking during the processing of table metadata when multiple changeset blocks are processed sequentially. Specifically, the vulnerability arises when an attacker supplies a crafted changeset that repeats a table name in a second block while simultaneously increasing the column count compared to the initial definition. This discrepancy triggers a logic error within the sessionUpdateFind routine, leading to insufficient memory allocation for internal tracking structures.
The technical mechanism of exploitation involves manipulating the size calculation for the aUpdateMask array, which is used internally by SQLite to track changes applied to specific columns during an update operation. When the second changeset block specifies more columns than were present in the first occurrence of that table name within the same session context, the application allocates memory based on the original, smaller column count rather than updating it to reflect the new maximum. Consequently, when sqlite3changeset_apply attempts to write status information for all columns defined in the second block using memset, it writes beyond the boundaries of the allocated heap buffer. This out-of-bounds write corrupts adjacent heap metadata or data structures, potentially leading to application crashes, arbitrary code execution if an attacker can control the overwritten memory contents and their placement within the heap layout, or denial of service conditions through segmentation faults.
From a risk perspective, this vulnerability falls under CWE-122: Heap-based Buffer Overflow, which is characterized by writing data beyond the allocated boundary of a buffer located in the heap memory space. The exploitation vector aligns with ATT&CK technique T1059.007: Command and Scripting Interpreter via SQLite commands if the application processes untrusted SQL changesets directly from external sources without adequate validation. While SQLite is primarily an embedded database engine, its widespread use in mobile applications, IoT devices, and desktop software means that a successful exploit could compromise data integrity or allow remote code execution depending on how the host application handles memory corruption events. The impact ranges from local denial of service to potential privilege escalation if combined with other heap exploitation techniques such as fastbin attacks or UAF scenarios facilitated by the corrupted state.
Mitigation strategies primarily involve upgrading SQLite to version 3.54.0 or later, where this logic error in sessionUpdateFind has been corrected to properly reallocate memory based on the maximum column count encountered across all changeset blocks for a given table name within a single session context. For applications unable to upgrade immediately due to dependency constraints, defensive programming practices should be implemented to validate changesets before passing them to sqlite3changeset_apply. This includes verifying that schema definitions remain consistent or strictly increasing in complexity when reusing table names across multiple blocks. Additionally, enabling Address Sanitizer during development and testing phases can help detect such heap overflows early in the software lifecycle. Security teams should also review any custom wrappers around SQLite session APIs to ensure they enforce strict validation of changeset structures against expected schema definitions before execution.