CVE-2026-43911

Description

Vaultwarden is a Bitwarden-compatible server written in Rust. Prior to 1.35.5, refresh tokens are not invalidated when the user's security_stamp is rotated by some security-sensitive operations (password change, KDF change, key rotation, email change, org admin password reset, emergency access takeover). This allows an attacker holding a previously obtained refresh token to maintain session access even after the user has taken action to secure their account. This vulnerability is fixed in 1.35.5.

Overview

State: PUBLISHED
Assigner (CNA): GitHub_M
CVSS severity: MEDIUM
CVSS score: 6.8 / 10
CVSS vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
Effective score: 6.8 / 10 MEDIUM source: CNA overview
CWE(s): CWE-613
Reserved: 2026-05-04
Published: 2026-05-11 23:54 UTC
Last updated: 2026-05-12 18:44 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/43xxx/CVE-2026-43911.json
Linked Threat: CVE-2026-43911 — CVE-2026-43911

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: 2026-05-11 23:20:21 UTC
NVD last modified: 2026-05-18 16:58:20 UTC
NVD CVSS v3.1: 6.8 / 10 MEDIUM source: security-advisories@github.com
NVD CVSS vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
Exploitability subscore: 1.6 / 10
Impact subscore: 5.2 / 10
EPSS score: 0.0003 (probability of exploitation in next 30 days)
EPSS percentile: 10.61% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24

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-2026-29339
Assigner: GitHub_M
Published: May 11, 2026, 9:54:41 PM
Updated: May 12, 2026, 4:44:07 PM
EUVD base score (CVSS 3.1): 6.8 / 10
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
EUVD-reported EPSS: 0.0400
Vendors: dani-garcia
Products: vaultwarden (< 1.35.5)

ENISA description: Vaultwarden is a Bitwarden-compatible server written in Rust. Prior to 1.35.5, refresh tokens are not invalidated when the user's security_stamp is rotated by some security-sensitive operations (password change, KDF change, key rotation, email change, org admin password reset, emergency access takeover). This allows an attacker holding a previously obtained refresh token to maintain session access even after the user has taken action to secure their account. This vulnerability is fixed in 1.35.5.

EUVD references (1)

https://github.com/dani-garcia/vaultwarden/security/advisories/GHSA-6j4w-g4jh-xjfx

Affected products (1)

Vendor	Product	Versions	Platforms
dani-garcia	vaultwarden	`< 1.35.5` (affected)	—

Affected products — CPE 2.3 (1) NVD

NVD's normalized CPE 2.3 matchers, used by vendor tools (vulnerability scanners, asset managers) for automated detection. Compare with the CNA's free-text "Affected products" section above.

cpe:2.3:a:dani-garcia:vaultwarden:*:*:*:*:*:*:*:*

Vendor references (1)

References embedded in the original CVE record by the assigning CNA.

https://github.com/dani-garcia/vaultwarden/security/advisories/GHSA-6j4w-g4jh-xjfx x_refsource_CONFIRM

MITRE references (1) cveawg.mitre.org

Pulled from MITRE's CVE Services API by the 🛰 Backfill from MITRE button.

https://github.com/dani-garcia/vaultwarden/security/advisories/GHSA-6j4w-g4jh-xjfx x_refsource_CONFIRM

Web references (3)

DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.

https://nvd.nist.gov/vuln/detail/CVE-2026-43911 tenable:nvd.nist.gov
https://www.cve.org/CVERecord?id=CVE-2026-43911 tenable:www.cve.org
https://www.first.org/epss/ tenable:www.first.org

NVD-tagged references (2)

Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.

https://github.com/dani-garcia/vaultwarden/security/advisories/GHSA-6j4w-g4jh-xjfx security-advisories@github.com ExploitMitigationVendor Advisory
https://github.com/dani-garcia/vaultwarden/security/advisories/GHSA-6j4w-g4jh-xjfx 134c704f-9b21-4f2e-91b3-4a467353bcc0 ExploitMitigationVendor Advisory

Remediations (16)

Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.

CVE-2026-43911 - Vulnerability Details - OpenCVE

web:app.opencve.io

The flaw affects every deployment of Vaultwarden released by dani‑garcia before version 1.35.5. All releases prior to 1.35.5 contain the bug; versions 1.35.5 and newer include the fix . Any server running a vulnerable version remains exposed until it is upgraded.

2026-05-23 20:59 UTC
CISA Warns of Exploited Microsoft Defender 0-Day Flaws

web:cyberpress.org

The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has added two actively exploited Microsoft Defender vulnerabilities to its Known Exploited Vulnerabilities (KEV) catalog, issuing an urgent remediation directive for federal agencies with a due date of June 3, 2026 .

2026-05-23 20:59 UTC
Microsoft Releases Out-of-Band Patch to Fix Critical RRAS RCE ...

web:cybersecuritynews.com

Microsoft released an out-of-band hotpatch update on March 13, 2026 , addressing serious security vulnerabilities in Windows 11 versions 24H2 and 25H2.

2026-05-23 20:59 UTC
Patch Tuesday, May 2026 Edition - Krebs on Security

web:krebsonsecurity.com

Microsoft expects that exploitation is more likely. May's Patch Tuesday is a welcome respite from April, which saw Microsoft fix a near-record 167 security flaws.

2026-05-23 20:59 UTC
Nvd - Cve-2026-43911

web:nvd.nist.gov

An official website of the United States government Here's how you know

2026-05-23 20:59 UTC
Security Update Guide - Microsoft

web:portal.msrc.microsoft.com

The Security Update Guide provides information on the latest Microsoft security updates, helping users understand and address potential vulnerabilities effectively.

2026-05-23 20:59 UTC
February's Patch Tuesday release fixes 59 flaws ... - Computerworld

web:www.computerworld.com

Each month, the team at Readiness analyzes the latest Patch Tuesday updates from Microsoft and provides detailed, actionable testing guidance. The company's Patch Tuesday release for February ...

2026-05-23 20:59 UTC
Microsoft fixes 167 security flaws in April, second biggest Patch ...

web:www.pcworld.com

This month's Patch Tuesday includes an actively exploited Office zero-day vulnerability and several critical RCE bugs in Windows and Remote Desktop.

2026-05-23 20:59 UTC
Microsoft Issues Massive Windows Patch for 160+ Bugs ... - TechRepublic

web:www.techrepublic.com

Microsoft's April 2026 Patch Tuesday fixes 165 vulnerabilities, including two zero-days, in one of the company's largest monthly security updates.

2026-05-23 20:59 UTC
Windows 11 April 2026 Update tested: What's new, improved and fixed

web:www.windowslatest.com

Windows 11 April 2026 update adds Narrator Copilot support, faster Settings, File Explorer fixes, and key security improvements.

2026-05-23 20:59 UTC
Microsoft and Adobe Patch Tuesday, April 2026 Security Update Review

web:blog.qualys.com

With Qualys Policy Audit's out-of-the-box mitigation or Compensatory Controls, which reduce the risk of a vulnerability being exploited because the remediation ( fix / patch ) cannot be done immediately, these security controls are not recommended by any industry standards, such as CIS and DISA-STIG.

2026-05-26 02:52 UTC
Security Update Guide - Microsoft

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.

2026-05-26 02:52 UTC
Microsoft April 2026 Patch Tuesday Update for Windows 11 and 10

web:windows101tricks.com

Microsoft's April 2026 Patch Tuesday update, released on April 14, 2026 , addresses 167 vulnerabilities, including two actively exploited zero-days and eight critical flaws. The update primarily targets Windows 10/11, Microsoft Office, SharePoint Server, and .NET Framework, and fixes issues such as Remote Code Execution (RCE) and Elevation of Privilege (EoP).

2026-05-26 02:52 UTC
CVE: Common Vulnerabilities and Exposures

web:www.cve.org

At cve .org, we provide the authoritative reference method for publicly known information-security vulnerabilities and exposures

2026-05-26 02:52 UTC
May 2026 Microsoft Patch Tuesday | Tenable®

web:www.tenable.com

Microsoft fixed 118 CVEs in the May 2026 Patch Tuesday, with no zero-days exploited in the wild or publicly disclosed for the first time since June 2024.

2026-05-26 02:52 UTC
Patch Tuesday May 2026: Security Updates & CVE Analysis

web:zecurit.com

Get the complete breakdown of Microsoft's May 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .

2026-05-26 02:52 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-43911.json.

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