CVE-2026-48796: CefSharp.Common path traversal in FolderSchemeHandlerFactory

CVE-2026-48796 · Severity: medium · CVSS 5.3 · Published 2026-08-18

CefSharp.Common is a library used to embed web browsers into Windows applications. A security flaw in how it handles local file requests allows an attacker to potentially access sensitive files on the user's computer that should be restricted. This occurs when the application is configured to serve files from a specific folder but fails to properly verify that requested files are actually inside that folder.

Technologies: CefSharp.Common (NuGet). Vendors: NuGet.

Quick answers

Is CVE-2026-48796 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-48796 being exploited in the wild.
How severe is CVE-2026-48796?
Medium severity, with a CVSS score of 5.3, published 18 August 2026.
Which products and versions are affected?
CefSharp.Common (NuGet) < 148.0.90, ECOSYSTEM:introduced=0,fixed=148.0.90.
Is there a fix for CVE-2026-48796?
Yes. CefSharp.Common (NuGet): upgrade to 148.0.90 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-48796 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-48796?
Check whether you run CefSharp.Common (NuGet) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • CefSharp.Common (NuGet): upgrade to 148.0.90 or later
    dotnet add package CefSharp.Common --version 148.0.90

Technical details

A path traversal vulnerability exists in CefSharp.Common's FolderSchemeHandlerFactory due to improper path validation. The component uses a raw string prefix check (StartsWith) on canonicalized paths to verify if a requested file resides within the configured root folder. Because it does not enforce a trailing directory separator, an attacker can use URL-encoded traversal sequences (e.g., ..%2f) to access sibling directories that share the same name prefix as the root folder (e.g., accessing 'www_secret' when the root is 'www'). Exploitation requires the attacker to influence the embedded browser to request a malicious URL handled by the affected scheme. The issue is resolved in version 148.0.90.

Affected products

  • CefSharp CefSharp.Common < 148.0.90

Identifiers

  • CVE-2026-48796
  • GHSA-85jm-cwp2-mvpv

Timeline

  • 2026-05-29: disclosed: Initial disclosure to GitHub Advisory Database
  • 2026-06-30: advisory: Advisory published and reviewed
  • 2026-06-30: patched: Fix available in version 148.0.90

References

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