CVE-2021-39136
Cross-site scripting vulnerability in file upload
CVE-2021-39136 is a high vulnerability (CVSS 8.7) in Basercms, published August 25, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.93%, the 60th percentile. Fixed in baserproject/basercms 4.5.1.
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- Required
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Cross-site scripting vulnerability in file upload
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.
- Record
CVE-2021-39136- CVSS 3.1
- 8.7 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
EUVDEUVD-2021-1745
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.
- Record
EUVD-2021-1745- CVSS 3.1
- 8.7 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-hgjr-632x-qpp3
Cross-site scripting vulnerability in file upload
There is a cross-site scripting vulnerability in file upload on the management system of baserCMS.
This is a vulnerability that needs to be addressed when the management system is used by an unspecified number of users. If you are eligible, please update to the new version as soon as possible.
Target
baserCMS 4.5.1 and earlier versions
Vulnerability
Execution of malicious JavaScript code may alter the display of the page or leak cookie information.
Countermeasures
Update to the latest version of baserCMS
Please refer to the next page for details. https://basercms.net/security/JVN_14134801
- Record
GHSA-hgjr-632x-qpp3- CVSS 3.1
- 8.7 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2021-39136- CVSS 3.1
- 8.7 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N - CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N - CVSS 2.0
- 3.5 Low
AV:N/AC:M/Au:S/C:N/I:P/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
OSV
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.
- Record
CVE-2021-39136- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N - Updated
- 2026-11-02
OSVGHSA-hgjr-632x-qpp3
Cross-site scripting vulnerability in file upload
There is a cross-site scripting vulnerability in file upload on the management system of baserCMS.
This is a vulnerability that needs to be addressed when the management system is used by an unspecified number of users. If you are eligible, please update to the new version as soon as possible.
Target
baserCMS 4.5.1 and earlier versions
Vulnerability
Execution of malicious JavaScript code may alter the display of the page or leak cookie information.
Countermeasures
Update to the latest version of baserCMS
Please refer to the next page for details. https://basercms.net/security/JVN_14134801
- Record
GHSA-hgjr-632x-qpp3- CVSS 3.1
- 8.7 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
baserproject/basercmsPackagist |
through 4.5.0 | 4.5.1 |
baserproject/basercmsPackagist |
before 4.5.1, plus listed versions 0.0.10.0.20.0.30.0.40.0.5 Show 45 moreShow less0.0.60.0.70.0.81.0.02.0.0-rc12.0.0-rc22.0.0-rc32.0.0-rc42.0.0-rc52.0.0-rc63.0.103.0.10.13.0.113.0.11.13.0.123.0.133.0.143.0.153.0.163.0.173.0.183.0.193.0.203.0.213.0.223.0.233.0.243.0.253.0.263.0.73.0.7.13.0.83.0.8.13.0.93.0.9.14.0.04.0.0-beta4.0.14.0.104.0.10.14.0.114.0.24.0.2.14.0.34.0.4 |
4.5.1 |
History
| When | Changed | Sources |
|---|---|---|
| 2026-11-03 | aliases | EUVD |
| 2026-11-02 | created | CVE List, GitHub Advisories, NVD, OSV |
References
github.com/baserproject/basercms/security/advisories/GHSA-hgjr-632x-qpp3
basercms.net/security/JVN_14134801
jvn.jp/en/jp/JVN14134801/index.html
nvd.nist.gov/vuln/detail/CVE-2021-39136
Left out here: 44 versions. The JSON record has them.