Vulnerability · Published Jul 22, 2026 · Assigned by mongodb
CVE-2026-13077Out-of-Bounds Heap Read in BSON CodeWScope Element Parsing via Malformed BSONColumn Data
High 7.1
In plain English
A high-severity out-of-bounds read in MongoDB Server from MongoDB. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 37% of all known vulnerabilities).
Official description
A missing bounds check in the BSON CodeWScope element accessors allows an attacker to trigger an out-of-bounds heap read via a crafted aggregation pipeline. The vulnerability can be exploited by an authenticated user by generating a malformed BSONColumn data containing a CodeWScope element, bypassing wire-level BSON validation. When the forged element is decompressed, the unchecked size value is used in pointer arithmetic, causing either a server crash or disclosure of adjacent heap memory contents.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| MongoDB | MongoDB Server | 7.0 – before 7.0.398.0 – before 8.0.288.2.0 – before 8.2.128.3.0 – before 8.3.7 |
Weakness: CWE-125 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H