CVE-2026-53956

Rattler vulnerable to package cache path traversal via conda package build string

Published Sep 9, 2026 CVSS 3.1 · 5.4 Medium EPSS < 1% KEV · Not listed
Description
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.

Analysis

AI-generated

Technical impact

Rattler, a common library in the Conda ecosystem, allowed the build string from package metadata to be incorporated into a cache path during materialization. A malicious or untrusted channel could embed path separators or traversal characters in that field, causing files to be written outside the intended cache directory. This flaw can lead to overwriting critical files or inserting malicious content into the Conda environment, thereby compromising integrity and potentially allowing privilege escalation if an attacker gains write access to sensitive locations.

Affected Systems

The vulnerability affects the rattler_cache component before version 0.9.0 and the py-rattler component before version 0.24.0. Any installation using these older versions and consuming packages from channels that are not curated by the official Conda team is at risk. The issue is confined to systems that rely on the default package cache path handling in these libraries.

Risk and Exploitability

The CVSS score of 5.4 indicates a moderate severity. There is no EPSS score available, and the vulnerability is not listed in the CISA KEV catalog. Exploitation requires a malicious or untrusted Conda channel to publish repodata containing a crafted build string; curated channels validate metadata and should not allow such malformed entries. The attack vector is therefore limited to compromised or fraudulent channels rather than arbitrary network exposure.

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

  • Upgrade rattler_cache to version 0.9.0 or later
  • Upgrade py-rattler to version 0.24.0 or later
  • Restrict Conda to use only trusted, curated channels

Generated by OpenCVE AI on September 9, 2026 at 22:48 UTC.

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-h672-p7h7-97v9 Rattler vulnerable to package cache path traversal via conda package build string
History
Type Values Removed Values Added
First Time appeared Conda
Conda py-rattler
Conda rattler
Vendors & Products Conda
Conda py-rattler
Conda rattler
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description 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.
Title Rattler vulnerable to package cache path traversal via conda package build string
Weaknesses CWE-22
CWE-73
References
Metrics cvssV3_1

{'score': 5.4, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L'}

Weaknesses
  • CWE-22

    Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

  • CWE-73

    External Control of File Name or Path

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Sep 10, 2026, 1:50 PM
Reserved
Jun 11, 2026, 3:50 PM
Status
Deferred
Published
Sep 9, 2026, 9:17 PM
Modified
Sep 10, 2026, 3:53 PM