CVE-2021-32661
CVE-2021-32661 is a medium-severity vulnerability in Linuxfoundation @backstage/plugin-techdocs with a CVSS 3.x base score of 6.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-434.
Key facts
- Severity: Medium (CVSS 3.x base score 6.8)
- CVSS v2: 4.9
- EPSS exploit prediction: 1% (65th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-434
- Affected product: Linuxfoundation @backstage/plugin-techdocs
- Published:
- Last modified:
Description
Backstage is an open platform for building developer portals. In versions of Backstage's Techdocs Plugin (`@backstage/plugin-techdocs`) prior to 0.9.5, a malicious internal actor can potentially upload documentation content with malicious scripts by embedding the script within an `object` element. This may give access to sensitive data when other users visit that same documentation page. The ability to upload malicious content may be limited by internal code review processes, unless the chosen TechDocs deployment method is to use an object store and the actor has access to upload files directly to that store. The vulnerability is patched in the `0.9.5` release of `@backstage/plugin-techdocs`.
Frequently asked questions
- What is CVE-2021-32661?
- Backstage is an open platform for building developer portals. In versions of Backstage's Techdocs Plugin (`@backstage/plugin-techdocs`) prior to 0.9.5, a malicious internal actor can potentially upload documentation content with malicious scripts by embedding the script within an `object` element. This may give access to sensitive data when other users visit that same documentation page. The ability to upload malicious content may be limited by internal code review processes, unless the chosen TechDocs deployment method is to use an object store and the actor has access to upload files directly to that store. The vulnerability is patched in the `0.9.5` release of `@backstage/plugin-techdocs`.
- How severe is CVE-2021-32661?
- CVE-2021-32661 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-32661 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-32661?
- CVE-2021-32661 affects Linuxfoundation @backstage/plugin-techdocs. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-32661?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2021-32661 published?
- CVE-2021-32661 was published on 2021-06-03 and last updated on 2026-06-17.
References
- https://github.com/backstage/backstage/commit/aad98c544e59369901fe9e0a85f6357644dceb5c
- https://github.com/backstage/backstage/releases/tag/release-2021-06-03
- https://github.com/backstage/backstage/security/advisories/GHSA-gg96-f8wr-p89f
Affected products (1)
- cpe:2.3:a:linuxfoundation:\@backstage\/plugin-techdocs:*:*:*:*:*:node.js:*:*
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