CVE-2018-1943

Vulnerability

IBM Cloud Private versions 3.1.0 and 3.1.1 are vulnerable to HTTP Host header injection due to improper validation of input [1]. By persuading a victim to visit a specially-crafted web page, a remote attacker could exploit this vulnerability to inject arbitrary HTTP headers [1]. This affects the IBM Cloud Private product line, specifically the management console or similar web-facing components that process the HTTP Host header.

Exploitation

To exploit the vulnerability, an attacker must persuade a victim to click a link or visit a web page that sends a crafted HTTP request to an IBM Cloud Private instance [1]. The attacker does not need prior network access to the system but requires the victim to have an active session or be able to access the IBM Cloud Private interface. The attack involves injecting a malicious Host header value into the request. The vulnerability requires no authentication beyond the victim's user session, and the attack complexity is low [1].

Impact

Successful exploitation allows the attacker to perform multiple types of attacks, including cross-site scripting (XSS), cache poisoning, or session hijacking [1]. These attacks can lead to information disclosure, impersonation of users, or manipulation of cached content. The CVSS base score is 5.4 (medium), with a vector of (CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N), indicating low confidentiality and integrity impact, but with scope change and low privileges required [1].

Mitigation

IBM Cloud Private 3.1.0 and 3.1.1 are affected. The vendor advisory does not list a specific fix version or workaround, stating "Workarounds and Mitigations: None" [1]. Users should check the IBM support page for updates (https://www.ibm.com/support/pages/node/871656) and apply any future patches [1]. Until a fix is released, organizations should consider limiting access to the IBM Cloud Private management interface and educating users to avoid clicking untrusted links.