theskumar python-dotenv up to 1.2.1 set_key/unset_key link following

CVSS Meta Temp Score
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CTI Interest Score
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5.8$0-$5k3.69

Summaryinfo

A vulnerability, which was classified as critical, was found in theskumar python-dotenv up to 1.2.1. This issue affects the function set_key/unset_key. Executing a manipulation can lead to link following. This vulnerability appears as CVE-2026-28684. The attack requires local access. There is no available exploit. You should upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in theskumar python-dotenv up to 1.2.1. This vulnerability affects the function set_key/unset_key. The manipulation with an unknown input leads to a link following vulnerability. The CWE definition for the vulnerability is CWE-59. The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is available at github.com. This vulnerability was named CVE-2026-28684 since 03/02/2026. The exploitation appears to be easy. Local access is required to approach this attack. Technical details are known, but there is no available exploit.

Upgrading to version 1.2.2 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch 790c5c02991100aa1bf41ee5330aca75edc51311 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.9
VulDB Meta Temp Score: 5.8

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.6
CNA Vector (GitHub_M): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Link following
CWE: CWE-59
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: python-dotenv 1.2.2
Patch: 790c5c02991100aa1bf41ee5330aca75edc51311

Timelineinfo

03/02/2026 CVE reserved
04/20/2026 +48 days Advisory disclosed
04/20/2026 +0 days VulDB entry created
04/20/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-mf9w-mj56-hr94
Status: Confirmed

CVE: CVE-2026-28684 (🔒)
GCVE (CVE): GCVE-0-2026-28684
GCVE (VulDB): GCVE-100-358318

Entryinfo

Created: 04/20/2026 19:48
Changes: 04/20/2026 19:48 (69)
Complete: 🔍
Cache ID: 216::103

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