JTL-Shop: Missing authentication allows unauthenticated maintenance mode toggle
Summary
JTL-Shop administration backend processes the plugin safe mode toggle on the admin logout route before checking authentication. An unauthenticated remote attacker can switch safe mode on or off with a single request, which deactivates all plugins (including payment and shipping integrations) and puts the shop into maintenance mode, causing a shop-wide denial of service. The attack can be automated against many installations. The vendor reports no confirmed exploitation as of 14 October 2026.
Affected
- JTL-Shop 5.3.0 to before 5.6.5 (per CNA record; vendor states 5.3.0 to 5.5.x are no longer patched, upgrade required)
- JTL-Shop 5.7.0 to before 5.7.5
- JTL-Shop 5.8.0 to before 5.8.2
- Shops hosted by JTL are reported as already fixed by the vendor
Fixed in
- Shop 5.6.5 (5.6 line)
- Shop 5.7.5 (5.7 line)
- Shop 5.8.2 (5.8 line)
- Versions 5.3.0 to 5.5.x: no fix on their own line; upgrade to a supported line
Workaround
- No vendor workaround known; upgrading is the documented fix.
- Restrict access to the admin backend at the reverse proxy or WAF where feasible.
- A WAF vendor claims protection, which is not independently verified.
Exploitation
- Public proof of concept: none known.
- Vendor: no evidence of exploitation as of 14 October 2026.
- CISA SSVC: automatable yes, technical impact partial. KEV status conflicting in sources; unverified.
Our recommendation
- Identify all JTL-Shop instances and versions, including third-party hosted ones.
- Upgrade to 5.6.5, 5.7.5 or 5.8.2 on the matching branch; move 5.3 to 5.5 installs to a supported line.
- Restrict admin backend exposure and review WAF options.
- Check access logs for requests to the admin logout route with safemode parameters and check plugin and maintenance mode status.
- Confirm final version wording with the vendor advisory.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- JTL-Software security advisory: Shop maintenance mode www.jtl-software.com
- VulDB entry 419796 vuldb.com
- CVE record (CVEProject cvelistV5) raw.githubusercontent.com
- JTL-Software security advisory: XSS (patch files) www.jtl-software.com
- JTL Guide: Safe mode FAQ guide.jtl-software.com
- Strix CVE details www.strix.ai
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 1 Nov 2026, 04:07.
Original description (NVD)
The authentication middleware of the JTL-Shop administration backend processes the plugin safe mode toggle on the admin logout route before checking whether the requesting user is authenticated. An unauthenticated remote attacker can therefore switch the shop's plugin safe mode on and off, which deactivates all installed plugins and their functionality, such as payment and shipping integrations, resulting in a shop-wide denial of service. The attack requires a single request and can be automated against many installations.
NVD references (1)
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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