SB2019122605 - Multiple vulnerabilities in JetBrains Kotlin Ktor

Description

This security bulletin contains information about 2 vulnerabilities.

1) Open redirect (CVE-ID: CVE-2019-19703)

CWE-ID: CWE-601 - URL Redirection to Untrusted Site ('Open Redirect')

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green

The vulnerability allows a remote attacker to redirect victims to arbitrary URL.

The vulnerability exists due to improper sanitization of user-supplied data. A remote attacker can create a link that leads to a trusted website, however, when clicked, redirects the victim to arbitrary domain.

Successful exploitation of this vulnerability may allow a remote attacker to perform a phishing attack and steal potentially sensitive information.

2) HTTP response splitting (CVE-ID: CVE-2019-19389)

CWE-ID: CWE-113 - Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Response Splitting')

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/U:Green

The vulnerability allows a remote attacker to perform HTTP splitting attacks.

The vulnerability exists due to software does not corrector process CRLF character sequences. A remote attacker can send specially crafted request containing CRLF sequence and make the application to send a split HTTP response.

Successful exploitation of the vulnerability may allow an attacker perform cache poisoning attack and XSS.

Remediation

Install update from vendor's website.

References

• https://github.com/ktorio/ktor/issues/1467
• https://blog.jetbrains.com/blog/2020/01/24/jetbrains-security-bulletin-q4-2019/
• https://gist.github.com/JLLeitschuh/6792947ed57d589b08c1cc8b666c7737
• https://github.com/ktorio/ktor/pull/1408
• https://twitter.com/JLLeitschuh/status/1210256191110230017?s=20