jquery.terminal self XSS on user input
Date: 2022-01
Affected: npm/jquery.terminal
Attack vector: xss
Category: vulnerability-disclosure
Severity: Low
CVE: CVE-2021-43862
CWE: CWE-79
CWE-80
CVSS: 3.7 (CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:N)

### Impact This is low impact and limited XSS, because code for XSS payload is always visible, but attacker can use other techniques to hide the code the victim sees. Also if the application use execHash option and execute code from URL the attacker can use this URL to execute his code. The scope is limited because the javascript code inside html attribute used is added to span tag, so no automatic execution like with `onerror` on images is possible. ### Patches Fixed version 2.31.1 ### Workarounds The user can use formatting that wrap whole user input and it's no op. ```javascript $.terminal.new_formatter([/([\s\S]+)/g, '[[;;]$1]']); ``` The fix will only work when user of the library is not using different formatters (e.g. to highlight code in different way). ### References The issue was reported here [jcubic/jquery.terminal#727](https://github.com/jcubic/jquery.terminal/issues/727) ### For more information If you have any questions or comments about this advisory: * Open an issue in [jcubic/jquery.terminal](https://github.com/jcubic/jquery.terminal) * Email us at [jcubic@onet.pl](mailto:jcubic@onet.pl)


Mitigations:

Architectural layers (MAESTRO):