The vulnerability CVE-2025-65922 affects Planka 2.0.0 due to the absence of X-Frame-Options and CSP frame-ancestors headers, which are security controls designed to prevent clickjacking and UI redressing attacks by restricting how the application can be embedded in iframes. Without these headers, attackers can embed the legitimate Planka interface within a malicious webpage iframe, potentially deceiving users into interacting with overlaid fake forms or UI elements crafted to harvest credentials or sensitive data. However, the supplier argues that Planka's use of SameSite=Strict cookies prevents authentication cookies from being sent in cross-origin iframe contexts, thus blocking session establishment and unauthorized actions. Additionally, browser-enforced Same-Origin Policy prevents the malicious parent frame from accessing or manipulating the iframe's content, limiting the attacker's ability to alter the legitimate UI or steal data directly. The vulnerability does not enable direct credential interception or unauthorized modifications but facilitates phishing attacks by leveraging user trust in the legitimate interface embedded within a malicious site. This attack vector requires user interaction and social engineering to succeed. No known exploits have been reported, and no patches or CVSS scores are currently available. The security impact is primarily related to phishing risk rather than technical compromise of the application itself.

For European organizations using Planka 2.0.0, this vulnerability primarily increases the risk of phishing attacks that could lead to credential theft or unauthorized access if users are tricked into entering sensitive information on maliciously framed pages. While direct compromise of the application or data integrity is unlikely due to SameSite cookie enforcement and browser policies, successful phishing could result in account takeover, data exposure, or lateral movement within organizational networks. This risk is heightened in sectors with high reliance on Planka for project management and collaboration, especially where users may be less aware of phishing tactics. The absence of technical exploitation means the impact depends heavily on user awareness and training. Organizations in Europe with remote or hybrid workforces may face increased exposure due to varied user environments and potential targeting by phishing campaigns. Overall, the impact is moderate but significant in terms of social engineering attack surface expansion.

European organizations should implement multiple layered defenses beyond generic advice: 1) Configure Planka or its hosting environment to include X-Frame-Options (e.g., DENY or SAMEORIGIN) and CSP frame-ancestors headers to prevent unauthorized framing. 2) Conduct targeted user awareness training focused on phishing risks associated with embedded content and UI redressing techniques, emphasizing verification of URLs and site authenticity. 3) Employ browser security policies via enterprise management tools to restrict iframe embedding and enforce strict cookie handling. 4) Monitor for suspicious login attempts or unusual access patterns that could indicate credential compromise. 5) Consider deploying multi-factor authentication (MFA) to reduce the impact of credential theft. 6) Regularly review and update security headers and cookie configurations as part of application security hygiene. 7) Encourage users to access Planka only via bookmarked or trusted URLs rather than links from untrusted sources. These measures collectively reduce the attack surface and mitigate phishing risks stemming from this vulnerability.