CVE-2025-4018 is a vulnerability identified in the 20120630 Novel-Plus software, specifically affecting the addCrawlSource function within the CrawlController.java file. The vulnerability arises due to missing authentication controls, allowing an unauthenticated attacker to remotely invoke this function without any form of access restriction. This flaw is present in the affected version 0e156c04b4b7ce0563bef6c97af4476fcda8f160 of Novel-Plus. The vulnerability was publicly disclosed on April 28, 2025, with a CVSS 4.0 base score of 6.9, categorized as medium severity. The CVSS vector indicates that the attack can be performed remotely (AV:N) with low attack complexity (AC:L), requires no privileges (PR:N), no user interaction (UI:N), and no confidentiality or availability impact, but it has a low impact on integrity (VI:L). The vulnerability does not require authentication or user interaction, making exploitation feasible remotely. The vendor was notified but did not respond or provide a patch, and no known exploits have been observed in the wild yet. The missing authentication in a controller function that likely manages crawl sources suggests potential unauthorized manipulation of the system's data ingestion or content sourcing mechanisms, which could lead to integrity issues or unauthorized data injection. Given the nature of the software (Novel-Plus), which appears to be related to content crawling or aggregation, this vulnerability could be leveraged to alter or inject malicious content or disrupt normal operations of content collection workflows.

For European organizations using Novel-Plus, this vulnerability poses a risk primarily to the integrity of their content aggregation or crawling processes. Unauthorized remote access to the addCrawlSource function could allow attackers to inject malicious or misleading data sources, potentially compromising the reliability of content or data pipelines. This could affect organizations relying on Novel-Plus for content aggregation, such as digital publishers, media companies, or research institutions. Although the confidentiality and availability impacts are minimal, the integrity compromise could lead to misinformation, reputational damage, or downstream processing errors. Additionally, if the injected sources contain malicious payloads, there could be secondary impacts on systems consuming the crawled data. The lack of vendor response and patch availability increases the risk exposure, especially for organizations that have not implemented compensating controls. The medium severity rating reflects the limited scope of impact but acknowledges the ease of exploitation due to no authentication or user interaction requirements.

1. Immediate mitigation should include implementing network-level access controls to restrict access to the Novel-Plus application, especially the CrawlController endpoints, to trusted internal IPs or VPN users only. 2. Deploy a Web Application Firewall (WAF) with custom rules to detect and block unauthorized requests targeting the addCrawlSource function or suspicious payloads. 3. If source code access is available, apply a manual patch by adding authentication and authorization checks to the addCrawlSource function to ensure only authorized users can invoke it. 4. Monitor application logs for unusual or unauthorized calls to the CrawlController endpoints to detect potential exploitation attempts. 5. Consider isolating the Novel-Plus service in a segmented network zone to limit lateral movement if compromised. 6. Engage in threat hunting activities focusing on anomalous crawl source additions or modifications. 7. Plan for an upgrade or migration to a patched version once the vendor releases a fix or consider alternative software solutions if the vendor remains unresponsive. 8. Educate relevant teams about this vulnerability and enforce strict operational procedures around content source management.