Medium 6.6Published Apr 20, 2026

CVE-2026-28684python-dotenv: Symlink following in set_key allows arbitrary file overwrite via cross-device rename fallback

Updated under an hour ago (Oct 26, 2026, 9:50 AM ET)

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It affects theskumar python-dotenv and 1 other product. Add what you run to find out whether that includes you.

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Every CVE for theskumar python-dotenv

Exploited in the last 30 days

python-dotenv reads key-value pairs from a .env file and can set them as environment variables. Prior to version 1.2.2, `set_key()` and `unset_key()` in python-dotenv follow symbolic links when rewriting `.env` files, allowing a local attacker to overwrite arbitrary files via a crafted symlink when a cross-device rename fallback is triggered. Users should upgrade to v.1.2.2 or, as a workaround, apply the patch manually.

CVSS: 6.6 MEDIUM (v3.1, CNA)CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:H/A:H
Weakness (CWE): CWE-59, CWE-61
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Apr 20, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

theskumar python-dotenv theskumar:python_dotenv (from the name)	before 1.2.2	CNA record
saurabh-kumar python-dotenv saurabh-kumar:python-dotenv	before 1.2.2	NVD

References

https://github.com/theskumar/python-dotenv/security/advisories/GHSA-mf9w-mj56-hr94x-refsource-confirm, exploit, patch, vendor-advisory
https://github.com/theskumar/python-dotenv/commit/790c5c02991100aa1bf41ee5330aca75edc51311x-refsource-misc, patch
https://github.com/theskumar/python-dotenv/releases/tag/v1.2.2x-refsource-misc, release-notes

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.