CVE-2018-13347: Mercurial Mercurial Mishandles Integer Addition And Vulnerability

CRITICAL
Advisory Identifier: GHSA-3mjj-mr4f-qxmx
Share
CVSS 9.8
CWE-190
Published
Advisory Summary

CVE-2018-13347 is a CRITICAL (CVSS 9.8) mercurial mishandles integer addition and vulnerability (CWE-190: Integer Overflow or Wraparound) affecting Mercurial libraries in the PyPI ecosystem. The issue involves mercurial mishandles integer addition and subtraction. Remediation is available by upgrading affected packages to version 4.6.1.

CVE-2018-13347 at a Glance

CVE Identifier CVE-2018-13347
GHSA Identifier GHSA-3mjj-mr4f-qxmx
Severity CRITICAL
CVSS v3.1 Base Score 9.8
CWE Classification CWE-190: Integer Overflow or Wraparound
Affected Product Mercurial
Package Ecosystem PyPI
Published Date
Last Updated

Security Impact

CVSS: 9.8

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity High (I:H)
Availability High (A:H)

How to Fix CVE-2018-13347

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

mercurial fixed: 4.6.1 
pip install mercurial>=4.6.1
Verify Direct and Transitive Dependencies

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

pip show mercurial

How to Check if You Are Affected

To determine whether your Python environment is affected by CVE-2018-13347, inspect your installed packages using pip:

pip show mercurial

Analyze the terminal output to locate any version of Mercurial in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 4.6.1), your application is affected.

Note: The pip show mercurial command checks currently installed packages in your active Python environment.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-190: Integer Overflow or Wraparound, where the product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. this occurs when an integer value is incremented to a value that is too large to store in the associated representation. when this occurs, the value may become a very small or negative number. In Mercurial, 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

`mpatch.c` in Mercurial before 4.6.1 mishandles integer addition and subtraction, aka OVE-20180430-0002.

CVE-2018-13347 Affected Mercurial Versions

1 component(s)
Fixed Versions:
4.6.1
Product / Package Ecosystem Affected Versions Fixed Version
mercurial
pypi/mercurial
PyPI
< 4.6.1
4.6.1

References

NVD — CVE-2018-13347 NVD
https://nvd.nist.gov/vuln/detail/CVE-2018-13347
access.redhat.com/errata/rhsa-2019:22... WEB
https://access.redhat.com/errata/RHSA-2019:2276
Mercurial Source Repository REPOSITORY
https://github.com/pypa/advisory-database/tree/main/vulns/mercurial/PYSEC-2018-89.yaml
lists.debian.org/debian-lts-announce... WEB
https://lists.debian.org/debian-lts-announce/2020/07/msg00032.html
Mercurial Security Information SECURITY
https://www.mercurial-scm.org/repo/hg-committed/log?rev=modifies%28%22mercurial%2Fmpatch.c%22%29+and+4.5%3A%3A
Mercurial Security Information SECURITY
https://www.mercurial-scm.org/repo/hg/rev/1acfc35d478c
Mercurial Security Information SECURITY
https://www.mercurial-scm.org/wiki/WhatsNew#Mercurial_4.6.1_.282018-06-06.29

Frequently Asked Questions

What is CVE-2018-13347?
CVE-2018-13347 is a security vulnerability in Mercurial involving Mercurial mishandles integer addition and subtraction under CWE-190: Integer Overflow or Wraparound.
Which Mercurial versions are affected?
Affected versions include releases prior to 4.6.1 across affected packages: mercurial.
What version fixes CVE-2018-13347?
Upgrading to 4.6.1 (or the latest patched release for your respective branch) resolves the vulnerability.
Is mercurial affected?
Yes, mercurial is affected in releases prior to 4.6.1. Upgrade your dependency to 4.6.1 or later.
What is the CVSS score of CVE-2018-13347?
CVE-2018-13347 has a CVSS v3.1 base score of 9.8 (CRITICAL) with vector string CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
What CWE is associated with CVE-2018-13347?
CVE-2018-13347 is classified under CWE-190: Integer Overflow or Wraparound (The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.).
How can I check PyPI dependencies for CVE-2018-13347?
Run the dependency tree command: 'pip show mercurial'. 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-3mjj-mr4f-qxmx",
  "modified" : "2024-09-25T19:57:21Z",
  "published" : "2022-05-13T01:24:55Z",
  "aliases" : [ "CVE-2018-13347" ],
  "summary" : "Mercurial mishandles integer addition and subtraction",
  "details" : "`mpatch.c` in Mercurial before 4.6.1 mishandles integer addition and subtraction, aka OVE-20180430-0002.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "mercurial"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "4.6.1"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2018-13347"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2019:2276"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pypa/advisory-database/tree/main/vulns/mercurial/PYSEC-2018-89.yaml"
  }, {
    "type" : "WEB",
    "url" : "https://lists.debian.org/debian-lts-announce/2020/07/msg00032.html"
  }, {
    "type" : "WEB",
    "url" : "https://www.mercurial-scm.org/repo/hg-committed/log?rev=modifies%28%22mercurial%2Fmpatch.c%22%29+and+4.5%3A%3A"
  }, {
    "type" : "WEB",
    "url" : "https://www.mercurial-scm.org/repo/hg/rev/1acfc35d478c"
  }, {
    "type" : "WEB",
    "url" : "https://www.mercurial-scm.org/wiki/WhatsNew#Mercurial_4.6.1_.282018-06-06.29"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-190" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2024-05-01T17:04:19Z",
    "nvd_published_at" : "2018-07-06T00:29:00Z"
  }
}