# CVE-2019-3902: mercurial: A flaw was found in Mercurial before 4.9

CVE-2019-3902 is fixed in 2 products on 1 platform, first by mercurial 4.5.3-1ubuntu2.2, released April 21, 2019. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2019-3902
- Priority: Routine
- CVSS: n/a (Medium)
- EPSS: 0.0136
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Apr 21, 2019

## Description

A flaw was found in Mercurial before 4.9. It was possible to use symlinks and subrepositories to defeat Mercurial's path-checking logic and write files outside a repository.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | mercurial Ubuntu 18.04.6 LTS (bionic) | 4.5.3-1ubuntu2.2 | [mercurial 4.5.3-1ubuntu2.2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-mercurial-4.5.3-1ubuntu2.2.md) | Apr 21, 2019 |
| Linux | mercurial-common Ubuntu 18.04.6 LTS (bionic) | 4.5.3-1ubuntu2.2 | [mercurial-common 4.5.3-1ubuntu2.2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-mercurial-common-4.5.3-1ubuntu2.2.md) | Apr 21, 2019 |

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