CVE-2025-7709 Overview
CVE-2025-7709 is an integer overflow vulnerability [CWE-190] in the SQLite FTS5 full-text search extension. The flaw occurs when the extension calculates the size of an array of tombstone pointers and truncates the value into a 32-bit integer. This truncation enables a pointer to partially attacker-controlled data to be written out of bounds. SQLite is embedded in countless applications, browsers, mobile platforms, and operating systems, making the FTS5 extension a broadly deployed attack surface. Successful exploitation can compromise integrity of the process using the affected database engine.
Critical Impact
An attacker able to influence FTS5 database contents can trigger an out-of-bounds write, corrupting memory in the host process and potentially altering execution integrity.
Affected Products
- SQLite FTS5 extension (see the GitHub Security Advisory for version details)
- Applications embedding vulnerable versions of SQLite with FTS5 compiled in
- Downstream distributions tracking SQLite releases prior to the fix
Discovery Timeline
- 2025-09-08 - CVE-2025-7709 published to the National Vulnerability Database
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-7709
Vulnerability Analysis
The defect resides in FTS5, the full-text search virtual table module distributed with SQLite. FTS5 maintains tombstone structures to track deleted rows within index segments. When FTS5 computes the byte size of the tombstone pointer array, the calculation overflows and is truncated to a 32-bit integer. The truncated value drives a smaller-than-required allocation. Subsequent writes then place pointers to partially attacker-controlled data past the end of the allocated buffer, producing a classic integer overflow leading to a heap out-of-bounds write.
Because SQLite ships inside browsers, mobile operating systems, desktop applications, and server software, the vulnerability affects a wide range of environments wherever untrusted FTS5 content or queries can be processed.
Root Cause
The root cause is arithmetic truncation during allocation sizing. Multiplying tombstone counts by pointer width produces a value that exceeds the range of a 32-bit integer. The result wraps, yielding an undersized allocation. FTS5 then writes pointer entries beyond the intended buffer boundary. This pattern is consistent with [CWE-190] Integer Overflow or Wraparound.
Attack Vector
Exploitation requires the ability to supply or influence FTS5 database content or queries processed by the vulnerable extension. The CVSS 4.0 vector indicates a network-reachable attack path with high complexity, low privileges, and required user interaction. Realistic scenarios include applications that open untrusted SQLite databases, sync FTS5 indexes from remote sources, or expose FTS5 features to remote input. Refer to the GitHub Security Advisory GHSA-v2c8-vqqp-hv3g and the OpenWall oss-security disclosure for detailed technical analysis. No public exploit is currently available.
Detection Methods for CVE-2025-7709
Indicators of Compromise
- Unexpected process crashes or heap corruption alerts in applications embedding SQLite with FTS5 enabled
- Malformed or oversized FTS5 index segments containing large tombstone counts
- Anomalous memory access violations correlated with SQLite FTS5 code paths
Detection Strategies
- Inventory applications and packages that link against SQLite and compile in the FTS5 extension, then compare against the fixed version noted in the vendor advisory
- Instrument software with AddressSanitizer or equivalent runtime memory-safety tooling during testing to surface the out-of-bounds write
- Monitor endpoint telemetry for repeated crashes in processes that parse untrusted SQLite databases
Monitoring Recommendations
- Alert on abnormal termination of applications known to consume external SQLite files, such as browsers, sync clients, and mobile app runtimes
- Track ingestion of SQLite artifacts from untrusted sources within email, web download, and file-share telemetry
- Correlate SQLite version data from software bill of materials with the fixed release identified in the advisory
How to Mitigate CVE-2025-7709
Immediate Actions Required
- Upgrade SQLite to the fixed version identified in the GitHub Security Advisory GHSA-v2c8-vqqp-hv3g
- Rebuild and redistribute applications that statically link SQLite once the patched version is integrated
- Restrict FTS5 use to trusted database inputs until patched builds are deployed
Patch Information
The SQLite maintainers addressed the integer overflow in the FTS5 tombstone size calculation. Consult the GitHub Security Advisory and the follow-up OpenWall oss-security notification for the exact commit references and fixed release versions. Distribution maintainers should track downstream package updates accordingly.
Workarounds
- Disable the FTS5 extension at compile time using SQLITE_ENABLE_FTS5=0 if full-text search is not required
- Reject or sandbox parsing of SQLite databases originating from untrusted sources
- Apply operating-system heap hardening features and enable exploit mitigations for processes that consume SQLite content
# Verify SQLite version in a running system
sqlite3 --version
# Confirm whether FTS5 is compiled into the shipping binary
sqlite3 :memory: "PRAGMA compile_options;" | grep -i FTS5
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
