Vulnerability · Published Sep 9, 2026 · Assigned by GitHub_M
CVE-2026-53956Rattler vulnerable to package cache path traversal via conda package build string
Medium 5.4
In plain English
A medium-severity path traversal in py-rattler from conda. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 26% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| PyPI | py-rattler | 0.24.0 | GHSA-h672-p7h7-97v9 |
| PyPI | py-rattler | 0.24.0 | PYSEC-2026-2970 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| conda | rattler_cache | < 0.9.0 |
| conda | py-rattler | < 0.24.0 |
Weakness: CWE-22, CWE-73 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L
References
- https://github.com/conda/rattler/security/advisories/GHSA-h672-p7h7-97v9 x_refsource_CONFIRM