CVE-2025-49325 is an Open Redirect vulnerability (CWE-601) identified in Automattic's Newspack Newsletters product, affecting versions up to 3.13.0. Open Redirect vulnerabilities occur when a web application accepts a user-controlled input that specifies a URL to which the application redirects the user, without sufficient validation. In this case, Newspack Newsletters improperly validates or sanitizes redirect URLs, allowing attackers to craft malicious links that appear to originate from a trusted domain but redirect users to untrusted, potentially malicious websites. This vulnerability can be exploited by attackers to conduct phishing attacks by leveraging the trust users place in the legitimate newsletter domain. The CVSS v3.1 base score is 4.7 (medium severity), reflecting that the vulnerability is remotely exploitable over the network without privileges (AV:N/AC:L/PR:N), but requires user interaction (UI:R) to trigger the redirect. The scope is changed (S:C), indicating that exploitation affects resources beyond the vulnerable component. The impact is limited to confidentiality (C:L), with no direct impact on integrity or availability. No known exploits are currently reported in the wild, and no patches have been linked yet. The vulnerability was published on June 6, 2025, shortly after being reserved on June 4, 2025. Given the nature of newsletters and their wide distribution, this vulnerability can be leveraged to deceive recipients into visiting malicious sites, potentially leading to credential theft or malware infection through social engineering. However, the lack of direct code execution or system compromise limits the severity to medium.

For European organizations using Automattic Newspack Newsletters, this vulnerability poses a significant phishing risk. Newsletters are often trusted communication channels for customers, partners, and employees. An attacker exploiting this vulnerability could craft malicious newsletter links that redirect users to fraudulent websites designed to steal credentials or deliver malware. This could lead to data breaches, financial fraud, or compromise of user accounts. Organizations in sectors with high reliance on newsletters for communication—such as media, publishing, education, and marketing—may face increased risk. Additionally, regulatory frameworks like GDPR impose strict requirements on protecting personal data; successful phishing attacks exploiting this vulnerability could lead to data exposure and regulatory penalties. The medium CVSS score reflects that while the vulnerability does not directly compromise system integrity or availability, the indirect impact via phishing can be substantial, especially if combined with other attack vectors. The requirement for user interaction means that user awareness and training remain critical factors in risk mitigation.

To mitigate CVE-2025-49325, European organizations should: 1) Immediately update Automattic Newspack Newsletters to the latest patched version once available; monitor Automattic’s official channels for patch releases. 2) Implement strict validation and sanitization of all URL parameters used in redirects within the newsletter system to ensure only trusted domains are allowed. 3) Employ Content Security Policy (CSP) headers and link scanning tools to detect and block malicious redirects in newsletters. 4) Educate newsletter recipients about the risk of phishing and encourage verification of URLs before clicking, especially those that redirect externally. 5) Use email security gateways with advanced phishing detection capabilities to filter malicious newsletter content before delivery. 6) Monitor newsletter traffic and logs for unusual redirect patterns or spikes in user complaints related to suspicious links. 7) Consider implementing multi-factor authentication (MFA) on critical systems to reduce the impact of credential theft resulting from phishing. These steps go beyond generic advice by focusing on both technical controls within the newsletter platform and organizational user awareness and detection mechanisms.