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CVE-2026-26266

Aliasvault cross-site scripting (XSS)

9.3 CRITICALEPSS 0.38%
  1. Published3 Mar 2026

Description

AliasVault is a privacy-first password manager with built-in email aliasing. A stored cross-site scripting (XSS) vulnerability was identified in the email rendering feature of AliasVault Web Client versions 0.25.3 and lower. When viewing received emails on an alias, the HTML content is rendered in an iframe using srcdoc, which does not provide origin isolation. An attacker can send a crafted email containing malicious JavaScript to any AliasVault email alias. When the victim views the email in the web client, the script executes in the same origin as the application. No sanitization or sandboxing was applied to email HTML content before rendering. This vulnerability is fixed in 0.26.0.[

CVSS 3.1 breakdown

Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionRequired
ScopeChanged
ConfidentialityHigh
IntegrityHigh
AvailabilityNone
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N

Affected products

Aliasvault< 0.26.0

Frequently asked

Is CVE-2026-26266 being actively exploited?

CVE-2026-26266 is not in the CISA KEV catalog. Its EPSS exploit probability is 0.38%.

How severe is CVE-2026-26266?

CVE-2026-26266 has a CVSS 3.1 base score of 9.3, rated critical. EPSS estimates a 0.38% probability of exploitation.

Which products are affected by CVE-2026-26266?

Affected products include Aliasvault.

How do I fix CVE-2026-26266?

Upgrade affected software to a fixed version, for example Aliasvault 0.26.0 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2026-26266 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

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Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.