Kimai has Server-Side Request Forgery in Invoice PDF Rendering via Markdown Image URLs

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS 4.0

5.3 · CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:N/SA:N · score source

EPSS

• CVE-2026-49865: 0.35% estimated exploitation activity in the next 30 days; percentile 28.76 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary Kimai 2.56.0 contains a server-side request forgery vulnerability in its invoice PDF preview and generation workflow. If an attacker can control Markdown content that is later rendered into an invoice PDF, such as Customer.invoiceText, the server-side PDF renderer will fetch remote image URLs embedded in Markdown image syntax. This allows the application server to issue outbound requests to attacker-controlled or internal targets during PDF rendering. The behavior can be used for internal network probing, server-side reachability checks, and potentially follow-on exploitation depending on deployment environment and accessible internal services. Details The vulnerable behavior occurs in the invoice rendering chain when user-controlled Markdown is transformed into HTML and then rendered by mPDF. - First, customer invoice text is copied into the invoice model. . Second, the default PDF invoice template renders that field through the Markdown-to-HTML filter. - Third, md2html…

Published by the source

10 Jul 2026, 16:04 UTC

Last modified by the source

10 Jul 2026, 16:04 UTC

Source last checked

26 Oct 2026, 14:50 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-pj8j-p4g4-4vw8

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# Patch Next advisory brief: CVE-2026-49865

Advisory: Kimai has Server-Side Request Forgery in Invoice PDF Rendering via Markdown Image URLs
IDs: CVE-2026-49865, GHSA-pj8j-p4g4-4vw8
Record: https://patchnext.com/advisories/cve-2026-49865 (revision 1, source checked 26 Oct 2026, 14:50 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.3)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: kimai/kimai 2.58.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- Packagist kimai/kimai: affected <= 2.57.0; fixed in 2.58.0

## Suggested inspection (read-only)
- Packagist kimai/kimai: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on kimai/kimai.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-pj8j-p4g4-4vw8 (GitHub-reviewed advisory GHSA-pj8j-p4g4-4vw8 lists affected ranges: Packagist kimai/kimai >=0 <=2.57.0)

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