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.
Published: 2026-07-22
Updated: 2026-07-23
Base Score: 7.5
Vector: CVSS2#AV:N/AC:L/Au:S/C:P/I:N/A:C
Severity: High
Base Score: 7.1
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H
Severity: High
Base Score: 7.1
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N
Severity: High
EPSS: 0.00404