CVE-2026-28684 (GCVE-0-2026-28684)

Vulnerability from cvelistv5 – Published: 2026-04-20 16:25 – Updated: 2026-04-20 17:43
VLAI
Title
python-dotenv: Symlink following in set_key allows arbitrary file overwrite via cross-device rename fallback
Summary
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.
Severity
6.6 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:H/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-20 17:43 UTC
CWE
  • CWE-59 - Improper Link Resolution Before File Access ('Link Following')
  • CWE-61 - UNIX Symbolic Link (Symlink) Following
Assigner
References
Impacted products
Vendor Product Version CPE status
theskumar python-dotenv Affected: < 1.2.2
guessed Create a notification for this product.
Show details on NVD website
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