Is pymongo safe ? 8 known vulnerabilities, worst severity HIGH.
// reach 21 direct dependencies
8 carry known advisories, worst CRITICAL
205 packages depend on it
an advisory here reaches each of them
// ai model usage No published models are known to use this package.
cvss CVSS v4.0 base score out of 10; GitHub rates it HIGH
epss chance of exploitation in 30 days, 1st percentile of all CVEs
xyz score CyberXYZ composite out of 10
fig. 01 — GHSA-98qm-wvgf-w4cf, the advisory selected below
// 8 advisories GHSA-98qm-wvgf-w4cf The C extension's BSON decoder scans a Regex element's pattern and flags strings with strlen before checking the document's remaining length, so a crafted truncated Regex element can read past the end of the caller's buffer. bson.decode and bson.decode_all accept mmap and array buffers, which carry no NUL sentinel; the read can cross into unmapped memory and kill the process with an uncatchable SI HIGH GHSA-vp6j-j7w5-5xjj PyMongo percent-decoded the entire host section of a connection string before splitting it into individual host:port entries. A percent-encoded , or : in a hostname therefore decoded into a real delimiter, injecting an additional attacker-chosen host and port into the client's seed list. HIGH GHSA-v4x9-3549-crwv An integer overflow in the BSON document encoding component of the MongoDB Python Driver's bundled native extension may occur when a single document is built from an unusually large amount of caller-supplied data. Size arithmetic is performed in a signed 32-bit type, and the guard meant to catch the overflow is written in a form whose behavior is not defined by the C language standard. A party wit HIGH GHSA-qx36-8mw2-4r3x PyMongo passed the KMS endpoint of a data key verbatim into parse_host(), which returns any string ending in .sock unchanged instead of validating it as a hostname and port. The driver's connection code then treats such an address as a Unix domain socket path and connects to it with AF_UNIX. Because the endpoint originates from masterKey.endpoint in a key vault document, a party who can write to t MODE GHSA-8fvv-fgr5-f8ch When reading/writing via an ID with the GridFS API, require an exact match on the given ID. Otherwise, if a Hash is given in place of the ID, it may be interpreted as criteria, overriding the ID match. MODE GHSA-m87m-mmvp-v9qm Versions of the package pymongo before 4.6.3 are vulnerable to Out-of-bounds Read in the bson module. Using the crafted payload the attacker could force the parser to deserialize unmanaged memory. The parser tries to interpret bytes next to buffer and throws an exception with string. If the following bytes are not printable UTF-8 the parser throws an exception with a single byte. MODE GHSA-cr6f-gf5w-vhrc Versions of the package pymongo before 4.6.3 are vulnerable to Out-of-bounds Read in the bson module. Using the crafted payload the attacker could force the parser to deserialize unmanaged memory. The parser tries to interpret bytes next to buffer and throws an exception with string. If the following bytes are not printable UTF-8 the parser throws an exception with a single byte. MODE GHSA-x33v-f3gp-gw2c bson/_cbsonmodule.c in the mongo-python-driver (aka. pymongo) before 2.5.2, as used in MongoDB, allows context-dependent attackers to cause a denial of service (NULL pointer dereference and crash) via vectors related to decoding of an "invalid DBRef." MODE // impact The C extension's BSON decoder scans a Regex element's pattern and flags strings with strlen before checking the document's remaining length, so a crafted truncated Regex element can read past the end of the caller's buffer. bson.decode and bson.decode_all accept mmap and array buffers, which carry no NUL sentinel; the read can cross into unmapped memory and kill the process with an uncatchable SIGSEGV. Any application decoding untrusted BSON from such buffers is affected — impact is availability only, since the out-of-bounds bytes are never returned as content. NUL-terminated buffers (bytes, bytearray) raise InvalidBSON at worst; the driver's own transport and pure-Python installs are not affected. All releases through 4.18.2 are affected when the C extension is loaded.
// patches Fixed in PyMongo 4.18.3. Malformed Regex elements now raise InvalidBSON on every accepted buffer type; valid documents decode unchanged.
// workarounds Decode untrusted BSON only from NUL-terminated buffers — bytes or bytearray — and copy mmap input first, e.g. bytes(mm[:size]).
// cvss v4.0 vector CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Attack vector Local
Attack complexity Low
Attack requirements Present
Privileges required None
User interaction None
Confidentiality (vulnerable system) None
Integrity (vulnerable system) None
Availability (vulnerable system) High
Confidentiality (subsequent systems) None
Integrity (subsequent systems) None
Availability (subsequent systems) None Checked 2026-11-06 at 22:18 UTC. The most recent advisory here was published 2026-10-27. Updated continuously from NVD, GHSA, OSV and CNA feeds.
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