CVE-2025-61983 is a heap-based buffer overflow vulnerability identified in the TP-Link Archer AX53 v1.0 router, specifically within its tmpserver modules. This vulnerability arises when an authenticated attacker on an adjacent network sends a specially crafted network packet containing an excessive number of fields with zero-length values. The malformed packet triggers a heap overflow, which can cause a segmentation fault leading to denial of service or potentially allow arbitrary code execution. The vulnerability affects firmware versions up to 1.3.1 Build 20241120. The attack vector requires the attacker to have high privileges (authenticated access) on an adjacent network segment, with no user interaction needed. The CVSS 4.0 base score of 7.3 reflects a high severity, driven by the high impact on confidentiality, integrity, and availability, and the complexity of the attack requiring high privileges and network adjacency. No known exploits are currently reported in the wild, but the vulnerability poses a significant risk due to the potential for remote code execution. The tmpserver module, likely responsible for temporary server functions or management interfaces, is the vulnerable component, indicating that exploitation could lead to control over router functions or network traffic manipulation. This vulnerability highlights risks in embedded network devices where buffer management errors can lead to critical security failures.

For European organizations, the impact of CVE-2025-61983 can be substantial. The Archer AX53 router is commonly deployed in small to medium business and home office environments, meaning that compromised devices could serve as entry points into corporate networks or disrupt critical connectivity. Successful exploitation could lead to denial of service, interrupting business operations, or enable attackers to execute arbitrary code, potentially allowing them to manipulate network traffic, intercept sensitive data, or pivot to other internal systems. Given the router’s role in network perimeter security, exploitation could undermine confidentiality, integrity, and availability of enterprise communications. The requirement for authenticated adjacent access limits remote exploitation but does not eliminate risk, especially in environments with weak internal network segmentation or compromised credentials. European entities with extensive remote or hybrid workforces may be particularly vulnerable if these routers are used in home offices connected to corporate VPNs. Additionally, the lack of current patches increases exposure until mitigations or firmware updates are released.

1. Immediately restrict administrative access to the Archer AX53 routers to trusted internal networks and disable remote management interfaces where possible. 2. Enforce strong authentication mechanisms and regularly update credentials to prevent unauthorized authenticated access. 3. Monitor network traffic for unusual patterns targeting the tmpserver modules or packets with abnormal field counts or zero-length values. 4. Segment internal networks to limit the ability of an attacker with adjacent access to reach vulnerable devices. 5. Deploy network intrusion detection/prevention systems (IDS/IPS) with signatures or anomaly detection tuned to detect exploitation attempts targeting heap overflow patterns. 6. Coordinate with TP-Link for timely firmware updates and apply patches as soon as they become available. 7. Educate users and administrators about the risks of using default or weak credentials and the importance of network hygiene. 8. Consider replacing affected devices with models that have a stronger security track record if patching is delayed or unavailable.