Out-of-bounds Read Affecting pymongo package, versions [3.9.0,4.18.3)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-PYTHON-PYMONGO-21756829
- published27 Oct 2026
- disclosed27 Oct 2026
- creditUnknown
Introduced: 27 Oct 2026
NewCVE-2026-106435 (opens in a new tab)How to fix?
Upgrade pymongo to version 4.18.3 or higher.
Overview
Affected versions of this package are vulnerable to Out-of-bounds Read via unbounded strlen scans in the BSON Regex element parser in bson/_cbsonmodule.c. When decoding a BSON document containing a Regex element, the C extension uses strlen to locate the NUL terminator of the pattern and flags strings without bounding the search to the remaining document bytes. An attacker who can supply a malformed BSON document without an embedded NUL can cause the parser to read beyond the document buffer, crashing the process.