CVE-2026-96808
📛 CVE Title
CVE-2026-96808
Description
In Flatpak before 1.18.1, the revokefs writer, used by the flatpak-system-helper to receive repository data from unprivileged callers, validated file paths by rejecting literal .. components but did not prevent symlink traversal. A malicious local user in an active local session could obtain two revokefs sessions via the system helper, create a symlink in one session pointing into the other session's directory, and retain a file descriptor through that symlink. This allowed the attacker to modify files belonging to a different revokefs session after they had been validated and imported by the system helper. In particular, an attacker could use this to tamper with ostree commit objects in the system repository after they passed signature verification, enabling root-controlled file writes to attacker-chosen paths and local root privilege escalation.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- mitre
- CVSS severity
- HIGH
- CVSS score
- 7.4 / 10
- CVSS vector
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H- Effective score
- 7.4 / 10 HIGH source: CNA overview
- CWE(s)
-
CWE-61 - Reserved
- 2026-09-23
- Published
- 2026-09-23 16:58 UTC
- Last updated
- 2026-09-23 18:22 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/96xxx/CVE-2026-96808.json
- Linked Threat
- CVE-2026-96808 — CVE-2026-96808
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
- 2026-09-23 17:17:25 UTC
- NVD last modified
- 2026-09-23 19:19:55 UTC
- NVD CVSS v3.1
- 7.4 / 10 HIGH source: cve@mitre.org
- NVD CVSS vector
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H- Exploitability subscore
- 1.4 / 10
- Impact subscore
- 5.9 / 10
NVD / KEV / EPSS data refreshed 2026-09-24 04:21 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-2026-85424 - Assigner
- mitre
- Published
- Sep 23, 2026, 4:58:37 PM
- Updated
- Sep 23, 2026, 6:22:46 PM
- EUVD base score (CVSS 3.1)
-
7.4 / 10
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - EUVD-reported EPSS
- 0.0000
- Vendors
- flatpak
- Products
-
flatpak (0 <1.18.1)
ENISA description: In Flatpak before 1.18.1, the revokefs writer, used by the flatpak-system-helper to receive repository data from unprivileged callers, validated file paths by rejecting literal .. components but did not prevent symlink traversal. A malicious local user in an active local session could obtain two revokefs sessions via the system helper, create a symlink in one session pointing into the other session's directory, and retain a file descriptor through that symlink. This allowed the attacker to modify files belonging to a different revokefs session after they had been validated and imported by the system helper. In particular, an attacker could use this to tamper with ostree commit objects in the system repository after they passed signature verification, enabling root-controlled file writes to attacker-chosen paths and local root privilege escalation.
EUVD references (1)
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| Flatpak | Flatpak |
0 (affected)
|
Linux |
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.qualys.com
The August 2026 Microsoft Patch Tuesday release delivers security fixes for vulnerabilities affecting a wide range of Microsoft products and services.
2026-09-24 11:07 UTC -
web:learn.microsoft.com
Learning path Learn how Microsoft supports secure software development as part of a cybersecurity solution - Training Secure software development means integrating security into each phase of your development lifecycle, from requirements analysis to maintenance. Microsoft provides many services that can help you develop more secure code and deploy a more secure application in the cloud. This ...
2026-09-24 11:07 UTC -
web:msrc.microsoft.com
Security Update Guide - Microsoft Security Response Center
2026-09-24 11:07 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 ...
2026-09-24 11:07 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.
2026-09-24 11:07 UTC -
web:www.aikido.dev
CVE remediation is fixing known flaws in the software you run. Why upgrading often fails, what remediation actually involves, and how backporting fixes it.
2026-09-24 11:07 UTC -
web:www.cisecurity.org
<p>Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for remote code execution. Successful exploitation of the most severe of these vulnerabilities could result in an attacker gaining the same privileges as the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or ...
2026-09-24 11:07 UTC -
web:www.computerworld.com
August's Patch Tuesday is a big one: 751 fixes, an exploited WinSock flaw and plenty of critical Windows, Office and Exchange issues.
2026-09-24 11:07 UTC -
web:www.forbes.com
Microsoft has patched 973 vulnerabilities, including actively exploited Windows CVE - 2026 -85880 and CVE - 2026 -81963 bugs. How should your organization respond to stay safe?
2026-09-24 11:07 UTC -
web:zecurit.com
Get the complete breakdown of Microsoft's September 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .
2026-09-24 11:07 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-96808.json.
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