CVE-2026-49865: Kimai SSRF in invoice PDF rendering via Markdown image URLs

CVE-2026-49865 · Severity: medium · CVSS 4 · Published 2026-09-11

Kimai, an open-source time-tracking application, is vulnerable to a security flaw in its invoice generation system. An attacker with the ability to edit customer or invoice text can embed malicious links that force the server to make unauthorized requests to internal or external networks. This could allow an attacker to probe your internal network for other vulnerable systems or sensitive data that is not normally accessible from the internet.

Technologies: Kimai, kimai/kimai (Packagist). Vendors: Kimai, Packagist.

Quick answers

Is CVE-2026-49865 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-49865 being exploited in the wild.
How severe is CVE-2026-49865?
Medium severity, with a CVSS score of 4, published 11 September 2026.
Which products and versions are affected?
Kimai <= 2.57.0; kimai/kimai (Packagist) <= 2.57.0, ECOSYSTEM:introduced=0,fixed=2.58.0.
Is there a fix for CVE-2026-49865?
Yes. kimai/kimai (Packagist): upgrade to 2.58.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-49865 attacked?
It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-49865?
Check whether you run Kimai or kimai/kimai (Packagist) 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

  • kimai/kimai (Packagist): upgrade to 2.58.0 or later
    composer require kimai/kimai:^2.58.0

Technical details

A Server-Side Request Forgery (SSRF) exists in Kimai's invoice rendering pipeline. When user-controlled Markdown (such as Customer.invoiceText) is processed, the md2html filter converts Markdown image syntax into HTML. The resulting HTML is then processed by the mPDF library, which attempts to fetch the remote image resources from the server side. An attacker with low privileges can exploit this to perform internal network scanning or reachability checks. The vulnerability is patched in version 2.58.0 by disabling Markdown images in favor of HTML links and implementing a specialized HttpClient (NoPrivateNetworkHttpClient) that restricts access to private network ranges.

Affected products

  • Kimai Kimai <= 2.57.0

Identifiers

  • CVE-2026-49865
  • GHSA-pj8j-p4g4-4vw8

Timeline

  • 2026-06-03: disclosed: Initial disclosure to vendor
  • 2026-07-10: advisory: GitHub Advisory published
  • 2026-07-10: patched: Fix released in version 2.58.0

References

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