---
id: CVE-2026-53956
title: >-
  Rattler vulnerable to package cache path traversal via conda package build
  string
summary: >-
  Rattler is a library that provides common functionality used within the conda
  ecosystem. `rattler_cache` prior to version 0.9.0 and `py-rattler` prior to
  version 0.24.0 were vulnerable to package-cache path traversal when handling
  packag…
severity: medium
cvss: 5.4
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L'
cvssSource: cna
cwe:
  - CWE-22
  - CWE-73
vendor: conda
product: rattler_cache
affected:
  - rattler_cache < 0.9.0
  - py-rattler < 0.24.0
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-10T13:50:50.765651Z'
published: '2026-09-09'
updated: '2026-09-10'
sourceUpdated: '2026-09-10T13:50:58.826Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-53956'
references:
  - url: 'https://github.com/conda/rattler/security/advisories/GHSA-h672-p7h7-97v9'
    label: 'https://github.com/conda/rattler/security/advisories/GHSA-h672-p7h7-97v9'
  - url: 'https://github.com/advisories/GHSA-h672-p7h7-97v9'
tags:
  - cve.org
  - nvd
  - ghsa
  - rust
aliases:
  - GHSA-h672-p7h7-97v9
ecosystem: rust
patched:
  - rattler_cache 0.9.0
  - py_rattler 0.24.0
ingestedAt: '2026-07-09T23:53:27.223Z'
epss: 0.0033
epssPercentile: 0.23425
---

## Overview

Rattler is a library that provides common functionality used within the conda ecosystem. `rattler_cache` prior to version 0.9.0 and `py-rattler` prior to version 0.24.0 were vulnerable to package-cache path traversal when handling package metadata from conda channels. During cache materialization, the `ratter_cache` code used the package record `build` string as part of a cache key that was joined into a filesystem path. A malicious or untrusted channel could publish repodata with path separators or traversal components in that field, causing package contents to be written outside the configured package cache directory. The issue requires use of a malicious or otherwise untrusted conda channel. Curated channels that validate package metadata are not expected to allow malformed build strings of this form. Users should upgrade to `rattler_cache` version 0.9.0 or `py-rattler` version 0.24.0 and avoid untrusted conda channels.

## Affected

- `rattler_cache < 0.9.0`
- `py-rattler < 0.24.0`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Package advisory (CVE-2026-53956)

Affected packages:

- `rattler_cache <= 0.8.2`
- `py_rattler <= 0.23.2`

Patched in:

- `rattler_cache 0.9.0`
- `py_rattler 0.24.0`

Source: https://github.com/advisories/GHSA-h672-p7h7-97v9