CVE-2026-106435
Application denial of service via out-of-bounds read in BSON Regex decoding in MongoDB Python Driver
MongoDB Python DriverRuntimes & languagesCVSS
5.9MediumExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.09%Chance of exploitation activity in the next 30 days, higher than 0% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed inNone listedNo source names a fixed version yet
What fixes it
No source in this snapshot names a fixed version.
Description
The MongoDB Python Driver's binary accelerator can read outside a buffer when an application decodes malformed BSON containing a truncated regular-expression element without a trailing NUL byte. An actor who can supply BSON to the documented decode or decode_all API can cause the application process to terminate when the C extension is loaded. The driver's normal database wire-protocol path does not reach this code.
Text from CVE List
Affected versions 1
- Python Driveraffected: 0.10.3 through 4.18.2CVE List