Bug 2394750 (CVE-2025-9086)

Summary:	CVE-2025-9086 curl: libcurl: Curl out of bounds read for cookie path
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	adudiak, crizzo, csutherl, dbosanac, gtanzill, jbuscemi, jclere, jmitchel, jreimann, kshier, mdessi, mrizzi, pcattana, pjindal, plodge, sdawley, stcannon, szappis, vchlup, yguenane
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	---
Doc Text:	An out of bounds read flaw has been discovered in the curl project. Under specific conditions the path comparison logic makes curl read outside a heap buffer boundary. This bug either causes a crash or it potentially makes the comparison come to the wrong conclusion and lets the clear-text site override the contents of the secure cookie, contrary to expectations and depending on the memory contents immediately following the single-byte allocation that holds the path.	Story Points:	---
Clone Of:		Environment:
Last Closed:		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:	2394877, 2394878, 2394879, 2394880, 2394881, 2394883, 2394885, 2394886, 2394882, 2394884
Bug Blocks:

Description OSIDB Bzimport 2025-09-12 06:01:28 UTC

1. A cookie is set using the `secure` keyword for `https://target`
2. curl is redirected to or otherwise made to speak with `http://target` (same
   hostname, but using clear text HTTP) using the same cookie set
3. The same cookie name is set - but with just a slash as path (`path='/'`).
   Since this site is not secure, the cookie *should* just be ignored.
4. A bug in the path comparison logic makes curl read outside a heap buffer
   boundary

The bug either causes a crash or it potentially makes the comparison come to
the wrong conclusion and lets the clear-text site override the contents of the
secure cookie, contrary to expectations and depending on the memory contents
immediately following the single-byte allocation that holds the path.

The presumed and correct behavior would be to plainly ignore the second set of
the cookie since it was already set as secure on a secure host so overriding
it on an insecure host should not be okay.