# CVE-2018-17983: PYSEC-2018-91 - cext/manifest.c in Mercurial before 4.7.2 has an out-of-bounds read during parsing of a malformed manifest entry.

Source: https://junglewise.ai/threats/cve-2018-17983-mercurial-out-of-bounds-read-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2018-10-04  
License: CC BY 4.0 with a link back

CVE-2018-17983 · Severity: low · CVSS 3 · Published 2018-10-04

cext/manifest.c in Mercurial before 4.7.2 has an out-of-bounds read during parsing of a malformed manifest entry.

Technologies: [mercurial (PyPI)](https://junglewise.ai/threats/technologies/mercurial). Vendors: [PyPI](https://junglewise.ai/threats/vendors/pypi).

## Quick answers

**Is CVE-2018-17983 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2018-17983 being exploited in the wild.

**How severe is CVE-2018-17983?** Low severity, with a CVSS score of 3, published 4 October 2018.

**Which products and versions are affected?** mercurial (PyPI) ECOSYSTEM:introduced=0,fixed=4.7.2.

**Is there a fix for CVE-2018-17983?** Yes. mercurial (PyPI): upgrade to 4.7.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2018-17983?** Check whether you run mercurial (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- mercurial (PyPI): upgrade to 4.7.2 or later

  ```sh
  pip install "mercurial>=4.7.2"
  ```


## Affected products

- mercurial (PyPI) ECOSYSTEM:introduced=0,fixed=4.7.2

## Identifiers

- CVE-2018-17983
- GHSA-p575-cf9h-wv42
- PYSEC-2018-91

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