CVE-2013-4103: Cryptocat before 2.0.22 has Remote Script Injection due to improperly sanitizing user input

PriorityP263critical9.8CVSS 3.1

AVNACLPRNUINSUCHIHAH

EXPLOIT

EPSS

6.87%

93.2th percentile

Cryptocat before 2.0.22 has Remote Script Injection due to improperly sanitizing user input

Affected

1 ranges

Vendor	Product	Version range	Fixed in
cryptocat_project	cryptocat	< 2.0.22	2.0.22

Detection & IOCsextracted from sources · hover to see the quote

urlHttp://example.come/data:image/foo;base64,PGh0bWw+PGlmcmFtZSBzcmM9Imh0dHA6Ly9ldmlsLmNvbS8iPjwvaWZyYW1lPjwvaHRtbD4NCg↗

→Detect data URI scheme with base64-encoded HTML/script payloads injected via user-supplied input in Cryptocat chat messages, particularly payloads using 'data:image/foo;base64,' with embedded iframe or HTML tags. ↗
→The base64 payload decodes to '<html><iframe src="http://evil.com/"></iframe></html>', indicating iframe injection as the attack vector. Monitor for data URI base64 strings that decode to HTML containing iframe or script tags. ↗
→Cryptocat versions prior to 2.0.22 are vulnerable; flag or block use of affected versions in enterprise environments. ↗

·The vulnerability exists because Cryptocat fails to properly sanitize user-supplied input, allowing remote script injection. The fix was introduced in version 2.0.22. ↗

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

nvdv2.07.5HIGHAV:N/AC:L/Au:N/C:P/I:P/A:P

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