CVE-2026-106557
Backstage: Improper input validation in TechDocs Markdown extension configuration
No known exploitation. EPSS puts it in the 21st percentile. No fix published yet.
What to do
No fixed build or workaround is published yet. Limit exposure and watch for a patch.
- BackstageAffected: < 1.50.5Upgrade to: not statedAffected: >= 1.51.0-next.0, < 1.54.6Upgrade to: not statedStated by: CVE record
- @backstage Plugin-techdocs-nodeAffected: < 1.14.6Upgrade to: not statedAffected: >= 1.15.0, < 1.15.4Upgrade to: not statedStated by: CVE record
Versions as the sources state them. Full version matrix after sign-in
What it is
From the CVE record
Backstage is an open framework for building developer portals. Prior to 1.14.6 and 1.15.4, the @backstage/plugin-techdocs-node package did not sufficiently validate TechDocs Markdown extension configuration. An authenticated user who can register or modify documentation sources may cause a TechDocs build to access resources outside the intended documentation boundary, potentially exposing backend-host data or internal network resources. This issue is fixed in versions 1.14.6 and 1.15.4 when pymdown-extensions 10.21.3 or later is also used, normally through mkdocs-techdocs-core 1.7.0 or later.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
0.3% chance of exploitation activity in the next 30 days, which ranks it in the 21st percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
5 events over 1 day, from the signal feeds we watch.
- Record updated
- Publishedweakness classified, att&ck mapped, record updated
Affected products
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N
Scored 7.7 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required LowRequires basic user-level privileges
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope ChangedThe exploit can affect other components (e.g. sandbox escape, host compromise from VM)
Impact if exploited
- Confidentiality HighTotal information disclosure — all data in the component is compromised
- Integrity NoneNo integrity impact
- Availability NoneNo availability impact
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
- CollectionT1005Data from Local Systemmedium confidence
- Command and ControlT1090Proxyhigh confidence
- DiscoveryT1083File and Directory Discoveryhigh confidence
- Initial AccessT1190Exploit Public-Facing Applicationmedium confidence
Sources
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