Bug 2566995

Summary:	CVE-2026-102925 uv: virtualenv: Arbitrary code execution via crafted paths in activation scripts [fedora-all]
Product:	[Fedora] Fedora	Reporter:	Oleg Sushchenko <osushche>
Component:	uv	Assignee:	Ben Beasley <code>
Status:	CLOSED NOTABUG	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	rawhide	CC:	code, mhroncok, python-packagers-sig, rust-sig
Target Milestone:	---	Keywords:	Security, SecurityTracking
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:	{"flaws": ["a6249085-bb04-4c98-8e48-d3ad02385335"]}
Fixed In Version:		Doc Type:	---
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2026-11-04 17:49:28 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:
Bug Blocks:	2543654

Description Oleg Sushchenko 2026-11-04 14:43:59 UTC

Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

virtualenv is a tool for creating isolated virtual python environments. Prior to 21.7.13, the generated activate (bash and zsh) and activate.fish scripts place values already escaped by shlex.quote inside an additional quoted context. In the bash and zsh script, a crafted virtual environment path reaches __VIRTUAL_ENV__ when a relocated environment's recorded directory is absent; in the fish script, crafted Tcl or Tk library paths reach __TCL_LIBRARY__ or __TK_LIBRARY__. The surplus quotes can terminate the data-only quoted run and leave shell metacharacters parsed as commands when a user sources the activation script, allowing code execution with that user's privileges. This issue is fixed in version 21.7.13.

Comment 1 Ben Beasley 2026-11-04 17:20:01 UTC

https://www.cve.org/CVERecord?id=CVE-2026-102925

I am not sure quite how to test this against uv. I don’t see any code in uv’s activation scripts that looks similar to the context of the fix in https://github.com/pypa/virtualenv/pull/3252, but that doesn’t mean that this defect doesn’t exist in a different form.

Based on recent reports like https://github.com/astral-sh/uv/issues/23060, this would also be “just a bug, not a security flaw” under uv’s threat model.

Comment 2 Miro Hrončok 2026-11-04 17:49:28 UTC

This one does not seem reproducible from uv.