Security readout for executives and security teams
Plain-English summary
This vulnerability can expose sensitive files from a Backstage server if TechDocs builds documentation locally from untrusted repositories. A malicious contributor could add symlinks that cause host file contents to be included in generated documentation visible to documentation viewers. Impact is confidentiality-only, but secrets or configuration files could be exposed.
Executive priority
Prioritize if Backstage is internet-accessible or widely used internally and TechDocs content can be modified by many contributors. The main business risk is leakage of host files, including secrets or configuration data. Upgrade or switch generation mode during the next security maintenance window.
Technical view
CVE-2026-25152 is a CWE-22 path traversal issue in @backstage/plugin-techdocs-node before 1.13.11 and 1.14.1. It affects Backstage deployments using techdocs.generator.runIn: local. MkDocs follows symlinks inside documentation during local generation, embedding referenced host file contents into generated HTML.
Likely exposure
Exposure is limited to Backstage instances using TechDocs local generation and processing documentation from sources where untrusted or lower-trust users can write. Instances using docker generation, or only fully trusted documentation repositories, have reduced exposure per the advisory.
Exploitation context
The source bundle does not show active exploitation, and KEV is false. Exploitation requires repository write access or influence over TechDocs source content, plus local generation. The CVSS vector indicates network reachability, low privileges, high attack complexity, no user interaction, and high confidentiality impact.
Researcher notes
Key gating conditions are local TechDocs generation, symlink-following during MkDocs build, and attacker-controlled documentation content. The advisory names fixed versions and workarounds. Do not assume all Backstage deployments are affected; configuration and repository trust boundaries determine practical exposure.
Mitigation direction
- Upgrade @backstage/plugin-techdocs-node to 1.13.11 or 1.14.1 or later.
- Switch TechDocs generation to runIn: docker where feasible.
- Restrict write access to TechDocs source repositories to trusted users only.
- Review the GitHub advisory for current vendor guidance and workarounds.
Validation and detection
- Inventory Backstage deployments using @backstage/plugin-techdocs-node.
- Check installed package versions against 1.13.11 and 1.14.1 fixed releases.
- Review app-config.yaml for techdocs.generator.runIn: local.
- Identify TechDocs repositories writable by untrusted or lower-trust users.
- Review generated TechDocs for unexpected embedded file content if exposure conditions existed.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-22: File access and web shell behavior lookup
File traversal and upload weaknesses can lead teams to review file, web shell, execution, and collection telemetry. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupFile access behavior lookup
The CVE wording references file access or upload behavior, so file telemetry and web shell review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupContainer behavior lookup
The affected technology mentions containers, so container-specific ATT&CK technique review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-25152 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 5.3 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N1.63.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
5.3MediumVector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/backstage/backstage/security/advisories/GHSA-w669-jj7h-88m9CVE reference · x_refsource_CONFIRM
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.