CVE-2026-90882
📛 CVE Title
Reflected arbitrary origins with credentials, allowing cross-origin reads of authenticated user data
Description
The open-vsx.org deployment returned Access-Control-Allow-Origin reflecting the requesting origin together with Access-Control-Allow-Credentials: true on the authenticated /user/ endpoints. A page on any origin could therefore issue credentialed requests to the service in a logged-in user's browser and read the responses. This exposed /user (login name, avatar, homepage, tokens URL), /user/tokens, /user/namespaces, /user/extensions, /user/search/{name} and /user/namespace/{name}/members, and — because /user/csrf was readable the same way — allowed the CSRF protection on write endpoints to be defeated. Chaining the two, an attacker page could call /user/token/create and exfiltrate a personal access token carrying publish and delete rights over the victim's namespaces. The headers were emitted by the CDN/edge layer, not by the application: the Open VSX software sets allowCredentials(true) in exactly one place, against a single exact origin derived from ovsx.webui.url, and defines no CORS mapping on /user/ beyond it. No configuration of the software produces origin reflection with credentials.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- eclipse
- CVSS severity
- HIGH
- CVSS score
- 8.7 / 10
- CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N- Effective score
- 8.7 / 10 HIGH source: CNA overview
- CWE(s)
-
CWE-942 - Reserved
- 2026-09-14
- Published
- 2026-09-22 09:27 UTC
- Last updated
- 2026-09-22 13:06 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/90xxx/CVE-2026-90882.json
- Linked Threat
- CVE-2026-90882 — Reflected arbitrary origins with credentials, allowing cross-origin reads of authenticated user data
NVD triage scoring NVD CVE 2.0
Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.
- NVD published
- 2026-09-22 10:17:10 UTC
- NVD last modified
- 2026-09-22 19:09:58 UTC
NVD / KEV / EPSS data refreshed 2026-09-23 02:34 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-84343 - Assigner
- eclipse
- Published
- Sep 22, 2026, 9:27:34 AM
- Updated
- Sep 22, 2026, 1:06:14 PM
- EUVD base score (CVSS 4.0)
-
8.7 / 10
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - EUVD-reported EPSS
- 0.0000
- Vendors
- Eclipse Foundation
- Products
-
open-vsx.org (29/04/2026 ≤07/09/2026)
- Aliases
-
GHSA-px7g-fw3g-w264
ENISA description: The open-vsx.org deployment returned Access-Control-Allow-Origin reflecting the requesting origin together with Access-Control-Allow-Credentials: true on the authenticated /user/ endpoints. A page on any origin could therefore issue credentialed requests to the service in a logged-in user's browser and read the responses. This exposed /user (login name, avatar, homepage, tokens URL), /user/tokens, /user/namespaces, /user/extensions, /user/search/{name} and /user/namespace/{name}/members, and — because /user/csrf was readable the same way — allowed the CSRF protection on write endpoints to be defeated. Chaining the two, an attacker page could call /user/token/create and exfiltrate a personal access token carrying publish and delete rights over the victim's namespaces. The headers were emitted by the CDN/edge layer, not by the application: the Open VSX software sets allowCredentials(true) in exactly one place, against a single exact origin derived from ovsx.webui.url, and defines no CORS mapping on /user/ beyond it. No configuration of the software produces origin reflection with credentials.
EUVD references (1)
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| Eclipse Foundation | open-vsx.org |
29/04/2026 (affected)
|
— |
Vendor references (1)
References embedded in the original CVE record by the assigning CNA.
Web references (0)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
No web references attached yet.
NVD-tagged references (1)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
Remediations (10)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:blog.checkpoint.com
CVE - 2026 -93616 is a newly discovered zero-day vulnerability in Security Management, and a fix is available now as part of this advisory. Fixes are available for both vulnerabilities. Customers running affected versions should install the applicable fixes immediately. Affected versions and remediation instructions are detailed below.
2026-09-23 15:14 UTC -
web:helpx.adobe.com
This page contains important information regarding security vulnerabilities that could affect specific versions of Adobe products. Use this information to take the prescribed corrective actions.
2026-09-23 15:14 UTC -
web:msrc.microsoft.com
The Microsoft Security Response Center (MSRC) investigates all reports of security vulnerabilities affecting Microsoft products and services, and provides the information here as part of the ongoing effort to help you manage security risks and help keep your systems protected.
2026-09-23 15:14 UTC -
web:sec.cloudapps.cisco.com
On September 16, 2026 , the Cisco Product Security Incident Response Team (PSIRT) published the advisories that are listed in the following tables. To remediate these vulnerabilities, Cisco strongly recommends that customers upgrade to the fixed software that is indicated in the advisories. For more information about changes in Cisco PSIRT vulnerability disclosure, see Strengthening the ...
2026-09-23 15:14 UTC -
web:senserva.com
Every Microsoft security patch (KB) and the CVEs it fixes, with severity, CVSS, and CISA KEV status. Cross-linked to the CVE reference.
2026-09-23 15:14 UTC -
web:support.servicenow.com
Due to additional analysis provided by the security researcher who discovered CVE - 2026 -6876, we have upgraded the severity rating of CVE - 2026 -6876 from High to Critical. This change affects only the severity
2026-09-23 15:14 UTC -
web:www.action1.com
In this issue: September 2026 Patch Tuesday updates from Microsoft, featuring zero-day vulnerabilities and critical security flaws.
2026-09-23 15:14 UTC -
web:www.ibm.com
Summary IBM WebSphere Application Server Liberty for IBM i is vulnerable to denial of service, remote code execution, and HTTP request smuggling when an attacker passes crafted requests to the web server or impersonates the application server and returns crafted responses [ CVE - 2026 -10852, CVE - 2026 -8858, CVE - 2026 -9072, CVE - 2026 -8633, CVE - 2026 -8620] as described in the vulnerability details section.
2026-09-23 15:14 UTC -
web:www.oracle.com
This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.
2026-09-23 15:14 UTC -
web:www.oracle.com
This Critical Patch Update contains 1448 new security patches across the product families listed below. Please note that a My Oracle Support (MOS) note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at July 2026 Critical Patch Update: Executive Summary and Analysis.
2026-09-23 15:14 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-90882.json.
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