Multiple vulnerabilities in JetBrains Kotlin Ktor

1) Open redirect

EUVDB-ID: #VU24896

Risk: Medium

CVSSv4.0: 2.7 [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]

CVE-ID: CVE-2019-19703

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

Exploit availability: No

Description

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.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Kotlin Ktor: 0.1.2 - 1.2.5

CPE2.3

• cpe:2.3:a:jetbrains_s.r.o.:kotlin_ktor:0.1.2:*:*:*:*:*:*:*
• cpe:2.3:a:jetbrains_s.r.o.:kotlin_ktor:0.1.3:*:*:*:*:*:*:*
• cpe:2.3:a:jetbrains_s.r.o.:kotlin_ktor:0.1.4:*:*:*:*:*:*:*

External links

https://github.com/ktorio/ktor/issues/1467
https://blog.jetbrains.com/blog/2020/01/24/jetbrains-security-bulletin-q4-2019/

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

2) HTTP response splitting

EUVDB-ID: #VU24895

Risk: Medium

CVSSv4.0: 2 [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]

CVE-ID: CVE-2019-19389

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

Exploit availability: No

Description

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.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Kotlin Ktor: 0.1.2 - 1.2.5

CPE2.3

• cpe:2.3:a:jetbrains_s.r.o.:kotlin_ktor:0.1.2:*:*:*:*:*:*:*
• cpe:2.3:a:jetbrains_s.r.o.:kotlin_ktor:0.1.3:*:*:*:*:*:*:*
• cpe:2.3:a:jetbrains_s.r.o.:kotlin_ktor:0.1.4:*:*:*:*:*:*:*

External links

https://gist.github.com/JLLeitschuh/6792947ed57d589b08c1cc8b666c7737
https://github.com/ktorio/ktor/pull/1408
https://twitter.com/JLLeitschuh/status/1210256191110230017?s=20

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.