CVE-2025-65922 identifies a security weakness in Planka 2.0.0 related to missing HTTP response headers that control framing behavior: specifically, the absence of X-Frame-Options and CSP frame-ancestors headers. These headers are critical for preventing clickjacking and UI redressing attacks by disallowing the application from being embedded within iframes on unauthorized domains. Without these protections, an attacker can embed the legitimate Planka interface inside a malicious webpage iframe, creating a deceptive environment to phish users by overlaying fake input forms or tricking users into interacting with the framed content under false pretenses. However, the vendor argues that Planka’s use of SameSite=Strict cookies prevents authentication cookies from being sent in cross-origin iframe contexts, thereby blocking session establishment and credential theft. Additionally, browser same-origin policies prevent the malicious parent page from accessing the iframe’s content, limiting the attacker's ability to manipulate or read data directly. The vulnerability does not allow unauthorized project or task modifications, and no integrity or availability impacts are present. Exploitation requires user interaction and trust in the malicious framing page, making it a phishing vector rather than a direct technical compromise. The CVSS 3.1 vector (AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N) reflects a network attack vector with low complexity, no privileges required, user interaction needed, unchanged scope, limited confidentiality impact, and no integrity or availability impact. No patches or known exploits are currently reported.

For European organizations using Planka 2.0.0, this vulnerability primarily increases the risk of phishing attacks that leverage UI redressing techniques. While the application itself is not directly compromised, users may be deceived into submitting sensitive credentials or information to attacker-controlled interfaces masquerading as the legitimate Planka application. This can lead to credential theft, unauthorized access to organizational resources, and potential lateral movement if attackers leverage stolen credentials. The impact on confidentiality is limited to user credentials or data voluntarily provided under deception, with no direct integrity or availability compromise of the Planka system. Given the reliance on user trust and interaction, the threat is more social-engineering oriented but can still result in significant security incidents, especially in environments where Planka is used for project management and collaboration involving sensitive data. Organizations with high user awareness and strong phishing defenses may mitigate risk, but those with less mature security cultures or remote workforces could be more vulnerable. The absence of technical exploitation avenues reduces the likelihood of automated attacks, but targeted phishing campaigns remain a concern.

European organizations should implement the following specific mitigations: 1) Configure Planka or its hosting environment to include X-Frame-Options (e.g., DENY or SAMEORIGIN) and/or Content Security Policy frame-ancestors directives to explicitly prevent unauthorized framing. 2) Educate users about the risks of phishing and UI redressing attacks, emphasizing caution when interacting with Planka interfaces embedded in unknown or suspicious websites. 3) Employ multi-factor authentication (MFA) for Planka access to reduce the impact of credential theft. 4) Monitor network traffic and logs for unusual access patterns or repeated failed login attempts that may indicate phishing or credential stuffing. 5) Use browser security features and extensions that warn users about framing or suspicious sites. 6) Regularly update Planka and related infrastructure to incorporate any future security patches addressing this or related vulnerabilities. 7) Consider deploying web application firewalls (WAF) with rules to detect and block framing attempts from unauthorized domains. 8) Conduct phishing simulation exercises to improve user resilience against social engineering attacks leveraging this vulnerability.