MongoDB PHP Driver OOB Read via BSON Decoding (CVE-2026-84968)
CVE-2026-84968 Published on September 3, 2026

Heap out-of-bounds read via corrupt nested BSON in field path error message
An out-of-bounds read in the BSON decoding component of the MongoDB PHP driver may allow an unauthenticated party who supplies specially formed input to have a small amount of adjacent process memory copied into an error message that is returned to application code. This may result in unintended disclosure of limited memory contents.

NVD

Vulnerability Analysis

CVE-2026-84968 is exploitable with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality and integrity and availability.

Attack Vector:
NETWORK
Attack Complexity:
LOW
Privileges Required:
NONE
User Interaction:
NONE

Weakness Type

Out-of-bounds Read

The software reads data past the end, or before the beginning, of the intended buffer. Typically, this can allow attackers to read sensitive information from other memory locations or cause a crash. A crash can occur when the code reads a variable amount of data and assumes that a sentinel exists to stop the read operation, such as a NUL in a string. The expected sentinel might not be located in the out-of-bounds memory, causing excessive data to be read, leading to a segmentation fault or a buffer overflow. The software may modify an index or perform pointer arithmetic that references a memory location that is outside of the boundaries of the buffer. A subsequent read operation then produces undefined or unexpected results.


Affected Versions

MongoDB PHP Driver: