CVE-2020-26282
Template Injection in BrowserUp Proxy
BrowserUp Proxy allows you to manipulate HTTP requests and responses, capture HTTP content, and export performance data as a HAR file. BrowserUp Proxy works well as a standalone proxy server, but it is especially useful when embedded in Selenium tests. A Server-Side Template Injection was identified in BrowserUp Proxy enabling attackers to inject arbitrary Java EL expressions, leading to unauthenticated Remote Code Execution (RCE) vulnerability. This has been patched in version 2.1.2.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Template Injection in BrowserUp Proxy
BrowserUp Proxy allows you to manipulate HTTP requests and responses, capture HTTP content, and export performance data as a HAR file. BrowserUp Proxy works well as a standalone proxy server, but it is especially useful when embedded in Selenium tests. A Server-Side Template Injection was identified in BrowserUp Proxy enabling attackers to inject arbitrary Java EL expressions, leading to unauthenticated Remote Code Execution (RCE) vulnerability. This has been patched in version 2.1.2.
- Record
CVE-2020-26282- CVSS 3.1
- 10.0 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N - Weakness
- CWE-74
- Updated
- 2026-11-02
EUVDEUVD-2020-1509
BrowserUp Proxy allows you to manipulate HTTP requests and responses, capture HTTP content, and export performance data as a HAR file. BrowserUp Proxy works well as a standalone proxy server, but it is especially useful when embedded in Selenium tests. A Server-Side Template Injection was identified in BrowserUp Proxy enabling attackers to inject arbitrary Java EL expressions, leading to unauthenticated Remote Code Execution (RCE) vulnerability. This has been patched in version 2.1.2.
- Record
EUVD-2020-1509- CVSS 3.1
- 10.0 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-wmfg-55f9-j8hq
Server-Side Template Injection
Impact
A Server-Side Template Injection was identified in BrowserUp Proxy enabling attackers to inject arbitrary Java EL expressions, leading to unauthenticated Remote Code Execution (RCE) vulnerability. This has been assigned CVE-2020-26282.
Patches
Effective Immediately, all users should upgrade to version 2.1.2 or higher.
Workarounds
None.
References
https://securitylab.github.com/research/bean-validation-RCE
For more information
If you have any questions or comments about this advisory:
- Open an issue in the BrowserUp Proxy repo
- Contact us via the BrowserUp website or email us at [email protected]
- Record
GHSA-wmfg-55f9-j8hq- CVSS 3.1
- 10.0 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N - Weakness
- CWE-74
- Updated
- 2026-11-02
NVD
BrowserUp Proxy allows you to manipulate HTTP requests and responses, capture HTTP content, and export performance data as a HAR file. BrowserUp Proxy works well as a standalone proxy server, but it is especially useful when embedded in Selenium tests. A Server-Side Template Injection was identified in BrowserUp Proxy enabling attackers to inject arbitrary Java EL expressions, leading to unauthenticated Remote Code Execution (RCE) vulnerability. This has been patched in version 2.1.2.
- Record
CVE-2020-26282- CVSS 3.1
- 10.0 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N - CVSS 3.1
- 10.0 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - CVSS 2.0
- 7.5 High
AV:N/AC:L/Au:N/C:P/I:P/A:P - Weakness
- CWE-74
- Updated
- 2026-11-02
OSV
BrowserUp Proxy allows you to manipulate HTTP requests and responses, capture HTTP content, and export performance data as a HAR file. BrowserUp Proxy works well as a standalone proxy server, but it is especially useful when embedded in Selenium tests. A Server-Side Template Injection was identified in BrowserUp Proxy enabling attackers to inject arbitrary Java EL expressions, leading to unauthenticated Remote Code Execution (RCE) vulnerability. This has been patched in version 2.1.2.
- Record
CVE-2020-26282- CVSS 3.1
- 10.0 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - Updated
- 2026-11-02
OSVGHSA-wmfg-55f9-j8hq
Server-Side Template Injection
Impact
A Server-Side Template Injection was identified in BrowserUp Proxy enabling attackers to inject arbitrary Java EL expressions, leading to unauthenticated Remote Code Execution (RCE) vulnerability. This has been assigned CVE-2020-26282.
Patches
Effective Immediately, all users should upgrade to version 2.1.2 or higher.
Workarounds
None.
References
https://securitylab.github.com/research/bean-validation-RCE
For more information
If you have any questions or comments about this advisory:
- Open an issue in the BrowserUp Proxy repo
- Contact us via the BrowserUp website or email us at [email protected]
- Record
GHSA-wmfg-55f9-j8hq- CVSS 3.1
- 10.0 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N - Weakness
- CWE-74
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
com.browserup:browserup-proxyMaven |
before 2.1.2 | 2.1.2 |
com.browserup:browserup-proxyMaven |
before 2.1.2, plus listed versions 1.1.01.2.01.2.12.0.02.0.12.1.02.1.1 |
2.1.2 |
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | ||
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2020-26282 is a critical vulnerability (CVSS 10.0) in Browserup Proxy, published December 24, 2020. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 4.83%, the 92nd percentile. Fixed in com.browserup:browserup-proxy 2.1.2.
References
github.com/browserup/browserup-proxy/security/advisories/GHSA-wmfg-55f9-j8hq
securitylab.github.com/research/bean-validation-RCE
nvd.nist.gov/vuln/detail/CVE-2020-26282