Bug 2499914 (CVE-2026-15076)

Summary:	CVE-2026-15076 io.vertx/vertx-web: Eclipse Vert.x Web Client: Information disclosure via improper cookie domain validation
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security <prodsec-ir-bot>
Status:	NEW ---	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	aazores, abrianik, ant, anujha, aschwart, asoldano, asyoung, aszczucz, avibelli, bbaranow, bgeorges, bmaxwell, boliveir, bstansbe, ccranfor, cescoffi, chfoley, cmah, dandread, dhanak, dkreling, dlofthou, drichtar, drosa, dsimansk, eaguilar, ebaron, ewittman, fmariani, fmongiar, ggrzybek, gmalinko, gsmet, gtanzill, istudens, ivassile, iweiss, janstey, jbuscemi, jhollowa, jmartisk, jmatsuok, jnethert, jpechane, jraez, jtolenti, jwon, kaycoth, kingland, lthon, manderse, mcarlett, mnovotny, mosmerov, mposolda, msvehla, nipatil, nwallace, olubyans, pantinor, parichar, pberan, pesilva, pgallagh, pjindal, pmackay, prichard, probinso, rgodfrey, rguimara, rhel-process-autobot, rkubis, rmartinc, rruss, rstancel, rstepani, rsvoboda, sausingh, sbiarozk, sdawley, ssilvert, sthirugn, sthorger, swoodman, tasato, tcunning, thjenkin, tqvarnst, vdosoudi, vmuzikar, watson-tool-maintainers, yfang
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	---
Doc Text:	A flaw was found in Eclipse Vert.x Web Client. The WebClientSession component does not properly validate the Domain attribute of a Set-Cookie response header against the originating server's domain. This vulnerability allows a remote attacker to inject a cookie scoped to an arbitrary third-party domain. When the victim application subsequently sends a request to the targeted domain, the injected cookie is presented, potentially leading to information disclosure and unauthorized access to sensitive data through the attacker's account on that service.	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:

Description OSIDB Bzimport 2026-07-14 09:01:20 UTC

In versions up to and including 4.5.29 (4.x branch) and 5.1.4 (5.x branch), the WebClientSession component of Eclipse Vert.x Web Client does not validate that the Domain attribute of a Set-Cookie response header matches the originating server's domain, in violation of RFC 6265 section 5.3.
An attacker who controls any server that the victim application contacts can inject a cookie scoped to an arbitrary third-party domain; because the session store performs no cross-domain ownership check, it stores and later transmits that cookie to the targeted domain.




When the victim application subsequently sends a request to the targeted domain using the same WebClientSession, it presents the attacker-injected cookie, causing the receiving service to process the request under the attacker's account. Sensitive data included in the victim application's requests, such as payment amounts, card details, or other API payloads, may then be accessible to the attacker through their own account on that service.

Comment 3 errata-xmlrpc 2026-07-30 07:45:13 UTC

This issue has been addressed in the following products:

  Red Hat Build of Apache Camel 4.18 for Quarkus 3.33

Via RHSA-2026:48118 https://access.redhat.com/errata/RHSA-2026:48118

Comment 4 errata-xmlrpc 2026-08-13 14:52:16 UTC

This issue has been addressed in the following products:

  Red Hat build of Apache Camel 4.18.3 for Spring Boot 3.5.16

Via RHSA-2026:54622 https://access.redhat.com/errata/RHSA-2026:54622