Cross-site Scripting (XSS)Weakness · CWE-79

CVE-2026-57958

MEDIUM · 6.1 CVSS v3.1 Published 2026-06-29
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
68/100
Remediation priority · Elevated
Remotely reachable No privileges 7 weeks old

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Mixpost through 2.6.0 contains a reflected cross-site scripting vulnerability that allows unauthenticated attackers to execute arbitrary JavaScript in authenticated users' browsers by crafting malicious OAuth callback URLs with unsanitized error query parameters. Attackers can exploit the OAuth callback controller's failure to sanitize error parameters before rendering them through Laravel flash messages via the Vue v-html directive to hijack authenticated user sessions or perform unauthorized actions.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Mixpost through 2.6.0 has a reflected XSS vulnerability in the OAuth callback controller. Unauthenticated attackers craft malicious URLs with unsanitized error query parameters that get rendered through Laravel flash messages via Vue's v-html directive, allowing arbitrary JavaScript execution in authenticated users' browsers for session hijacking.

MitigationSanitize all error query parameters in the OAuth callback controller before storing them in flash messages, or replace v-html with v-text/v-pre for displaying OAuth error messages to prevent HTML injection.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Determine Mixpost installed version
    Check the application's version file, composer.json, or admin interface version display. Compare against the affected range: any version through 2.6.0.
    Affected if Installed version is 2.6.0 or earlier
  2. Verify OAuth authentication is enabled
    Check if any OAuth providers (social login) are configured in the application settings or configuration files.
    Affected if OAuth providers are configured and active
  3. Inspect OAuth callback controller for flash message usage
    Locate the OAuth callback controller handling error responses. Check if error query parameters from the OAuth provider are stored directly into Laravel flash messages without sanitization.
    Affected if Error parameters from OAuth callbacks are stored in flash messages without input sanitization
  4. Check Vue template for v-html usage with OAuth errors
    Inspect the view templates that render OAuth error messages. Look for v-html directive binding to flash message data containing OAuth error parameters.
    Affected if v-html is used to display OAuth error messages from flash data

A user is affected if running Mixpost version 2.6.0 or earlier with OAuth providers enabled, where the OAuth callback controller stores unsanitized error parameters in flash messages rendered via v-html.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Sanitize all error query parameters in the OAuth callback controller before storing them in flash messages, or replace v-html with v-text/v-pre for displaying OAuth error messages to prevent HTML injection.

Have this fixed Scoped from the published advisory
  • Consultation1.0 h
  • Implementation2.0 h
  • Testing3.0 h
  • Review / QA1.0 h
7.0 hours of engineering $1,190
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Scan for this in your stack

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-57958 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
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