Bug 2548264 (CVE-2026-106435)

Summary: CVE-2026-106435 pymongo: pymongo: Denial of Service via out-of-bounds read during malformed BSON decoding
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: eglynn, jjoyce, jpretori, jschluet, lhh, mburns, mgarciac
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in pymongo. An attacker who can supply crafted BSON (Binary JSON) data to the application's decoding functions can trigger an out-of-bounds read when parsing a truncated regular expression missing a terminating null byte. This flaw can cause the application process to terminate unexpectedly when the C extension accelerator is enabled, resulting in a Denial of Service (DoS).
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2549652, 2549653    
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Description OSIDB Bzimport 2026-10-08 20:31:38 UTC 
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.