GHSA-mj73-j457-8x9q: maxminddb's `Reader :open_mmap` Unsoundly Marks Unsafe Memmap Vulnerability

LOW
Share
CWE-915
Published
Advisory Summary

GHSA-mj73-j457-8x9q is a LOW :open_mmap` unsoundly marks unsafe memmap vulnerability (CWE-915: Improperly Controlled Modification of Dynamically-Determined Object Attributes) affecting maxminddb's `Reader libraries in the crates.io ecosystem. The issue involves :open_mmap` unsoundly marks unsafe memmap operation as safe. Remediation is available by upgrading affected packages to version 0.27.0.

GHSA-mj73-j457-8x9q at a Glance

CVE Identifier N/A
GHSA Identifier GHSA-mj73-j457-8x9q
Severity LOW
CVSS v3.1 Base Score N/A
CWE Classification CWE-915: Improperly Controlled Modification of Dynamically-Determined Object Attributes
Affected Product maxminddb's `Reader
Package Ecosystem crates.io
Published Date
Last Updated

How to Fix GHSA-mj73-j457-8x9q

To remediate this vulnerability, upgrade all affected maxminddb's `Reader dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

maxminddb fixed: 0.27.0 
Upgrade maxminddb to 0.27.0
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

inspect dependencies for maxminddb

How to Check if You Are Affected

To determine whether your application is affected by GHSA-mj73-j457-8x9q, inspect your project dependencies for maxminddb's `Reader:

inspect dependencies for maxminddb

Analyze the terminal output to locate any version of maxminddb's `Reader in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.27.0), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-915: Improperly Controlled Modification of Dynamically-Determined Object Attributes, where the product receives input from an upstream component that specifies multiple attributes, properties, or fields that are to be initialized or updated in an object, but it does not properly control which attributes can be modified. In maxminddb's `Reader, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

maxminddb prior to version 0.27 declared `Reader::open_mmap` as safe despite wrapping an inherently unsafe memmap2 operation with no extra step done to guarantee safety. This could have led to undefined behaviour if the file were to be modified on disk while the memory map was still active.

GHSA-mj73-j457-8x9q Affected maxminddb's `Reader Versions

1 component(s)
Fixed Versions:
0.27.0
Product / Package Ecosystem Affected Versions Fixed Version
maxminddb
 crates.io
≥ 0.11.0
< 0.27.0
0.27.0

References

maxminddb's `Reader Source Repository REPOSITORY
https://github.com/oschwald/maxminddb-rust/issues/86
Security Fix Commit FIX COMMIT
https://github.com/oschwald/maxminddb-rust/commit/98f0e4fff9678c841ed33f3b8a46322f6163c32a
maxminddb's `Reader Source Repository REPOSITORY
https://github.com/oschwald/maxminddb-rust
rustsec.org/advisories/rustsec-... WEB
https://rustsec.org/advisories/RUSTSEC-2025-0132.html

Frequently Asked Questions

What is GHSA-mj73-j457-8x9q?
GHSA-mj73-j457-8x9q is a security vulnerability in maxminddb's `Reader involving :open_mmap` unsoundly marks unsafe memmap operation as safe under CWE-915: Improperly Controlled Modification of Dynamically-Determined Object Attributes.
Which maxminddb's `Reader versions are affected?
Affected versions include releases prior to 0.27.0 across affected packages: maxminddb.
What version fixes GHSA-mj73-j457-8x9q?
Upgrading to 0.27.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is maxminddb affected?
Yes, maxminddb is affected in releases prior to 0.27.0. Upgrade your dependency to 0.27.0 or later.
What CWE is associated with GHSA-mj73-j457-8x9q?
GHSA-mj73-j457-8x9q is classified under CWE-915: Improperly Controlled Modification of Dynamically-Determined Object Attributes (The product receives input from an upstream component that specifies multiple attributes, properties, or fields that are to be initialized or updated in an object, but it does not properly control which attributes can be modified.).
How can I check crates.io dependencies for GHSA-mj73-j457-8x9q?
Run the dependency tree command: 'inspect dependencies for maxminddb'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-mj73-j457-8x9q",
  "modified" : "2025-12-11T17:28:12Z",
  "published" : "2025-12-02T00:29:11Z",
  "aliases" : [ ],
  "summary" : "maxminddb's `Reader::open_mmap` unsoundly marks unsafe memmap operation as safe",
  "details" : "maxminddb prior to version 0.27 declared `Reader::open_mmap` as safe despite wrapping an inherently unsafe memmap2 operation with no extra step done to guarantee safety. This could have led to undefined behaviour if the file were to be modified on disk while the memory map was still active.",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "crates.io",
      "name" : "maxminddb"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0.11.0"
      }, {
        "fixed" : "0.27.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/oschwald/maxminddb-rust/issues/86"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/oschwald/maxminddb-rust/commit/98f0e4fff9678c841ed33f3b8a46322f6163c32a"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/oschwald/maxminddb-rust"
  }, {
    "type" : "WEB",
    "url" : "https://rustsec.org/advisories/RUSTSEC-2025-0132.html"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-915" ],
    "severity" : "LOW",
    "github_reviewed" : true,
    "github_reviewed_at" : "2025-12-02T00:29:11Z",
    "nvd_published_at" : null
  }
}