The year 2025 marked one of the most aggressive periods of vulnerability exploitation in modern cybersecurity history. Threat actors—ranging from ransomware gangs to state-sponsored APT groups—actively weaponized critical flaws across web frameworks, operating systems, cloud services, VPN appliances, and industrial platforms.
This article analyzes the top 16 most exploited CVEs of 2025, focusing on real-world exploitation, technical impact, and why organizations must treat these vulnerabilities as urgent security priorities.
CVE-2025-55182 – React2Shell (React Server Components RCE)
- Severity: Critical (CVSS 10.0)
- Affected: React Server Components (React 19.x), Next.js applications
- Attack Vector: Network / Web Application (Unauthenticated)
CVE-2025-55182 fundamentally reshaped the security perception of modern JavaScript frameworks. The vulnerability originates from unsafe deserialization within the React Server Components Flight protocol, where untrusted payloads are processed server-side without adequate validation. Because React Server Components are designed to serialize component trees across the network, this flaw created a powerful and highly exploitable attack surface.
What made React2Shell especially dangerous was its default exploitability. Applications created using standard Next.js configurations were vulnerable without any developer misconfiguration. Attackers could execute privileged JavaScript on the server, often escalating to full system compromise. The rapid appearance of proof-of-concept exploits and real-world attacks demonstrated how deeply supply-chain dependencies amplify security risks at internet scale.
CVE-2025-32433 – Erlang/OTP SSH Pre-Authentication RCE
- Severity: Critical (CVSS 10.0)
- Affected: Erlang/OTP SSH daemon
- Attack Vector: Network / SSH Protocol (Pre-authentication)
This vulnerability exposed a critical flaw in how the Erlang/OTP SSH daemon handled protocol messages before authentication. Attackers could send specially crafted SSH channel messages that triggered command execution prior to any credential validation.
Because Erlang underpins telecommunications systems, messaging platforms, IoT infrastructure, and financial services, exploitation had a disproportionately high impact. Many affected SSH daemons ran with elevated privileges, meaning successful exploitation frequently resulted in immediate root access. The vulnerability underscored the catastrophic potential of protocol-level flaws in infrastructure software.
CVE-2025-59287 – Microsoft WSUS Deserialization RCE
- Severity: Critical (CVSS 9.8)
- Affected: Microsoft Windows Server Update Services (WSUS)
- Attack Vector: Network / WSUS HTTP(S) (Ports 8530, 8531)
CVE-2025-59287 highlighted the dangers of legacy serialization mechanisms in enterprise services. Unsafe deserialization within WSUS allowed unauthenticated attackers to execute arbitrary code as SYSTEM by sending crafted requests to exposed endpoints.
Because WSUS is widely trusted and often loosely monitored inside enterprise networks, compromise provided attackers with deep internal visibility and powerful lateral movement opportunities. Exploitation commonly led to reconnaissance, credential harvesting, and persistent access across Windows domains.
CVE-2025-5777 – CitrixBleed 2
- Severity: Critical (CVSS 9.3)
- Affected: Citrix NetScaler ADC and Gateway
- Attack Vector: Network / VPN Gateway (Unauthenticated)
CitrixBleed 2 was an out-of-bounds read vulnerability that allowed attackers to leak sensitive memory from NetScaler devices, including session cookies and authentication tokens. Rather than executing code directly, attackers hijacked legitimate VPN sessions and bypassed multi-factor authentication.
This vulnerability effectively erased the boundary between external and internal networks. Once attackers obtained valid session tokens, they moved laterally without triggering authentication logs, making detection extremely difficult. The flaw reinforced the long-standing architectural risks in VPN gateway memory handling.
CVE-2025-20333 – Cisco ASA/FTD VPN Remote Code Execution
- Severity: Critical (CVSS 9.9)
- Affected: Cisco ASA, Cisco Firepower Threat Defense
- Attack Vector: Network / VPN Authentication Interface
This buffer overflow vulnerability allowed authenticated VPN users to execute arbitrary code as root on Cisco security appliances. The flaw was actively exploited by state-sponsored actors as part of long-term espionage campaigns.
Compromising perimeter firewalls provided attackers with unparalleled network visibility, enabling traffic inspection, credential interception, and stealthy persistence. The incident demonstrated that security appliances themselves are now prime high-value targets.
CVE-2025-20362 – Cisco ASA Authorization Bypass
- Severity: Medium (CVSS 6.5)
- Affected: Cisco ASA, Cisco Firepower Threat Defense
- Attack Vector: Network / Firewall Management Interface
Although moderate in isolation, this missing authorization vulnerability enabled unauthenticated access to restricted firewall endpoints. In real-world attacks, it was used as an initial foothold and chained with CVE-2025-20333 to achieve full device compromise.
The vulnerability illustrates how lower-severity flaws can become critical when combined strategically by advanced attackers.
CVE-2025-9242 – WatchGuard Firebox IKEv2 RCE
- Severity: Critical (CVSS 9.3)
- Affected: WatchGuard Firebox, Fireware OS
- Attack Vector: Network / IKEv2 VPN Protocol
This stack-based buffer overflow in the IKE daemon allowed unauthenticated attackers to execute arbitrary code using only a small number of crafted VPN packets. The vulnerable code executed early in the IKE handshake, making exploitation fast and reliable.
Researchers noted the absence of modern exploit mitigations, which significantly lowered the barrier to weaponization. Successful exploitation granted full control of firewall devices, undermining perimeter security entirely.
CVE-2025-12480 – Gladinet Triofox Access Control Bypass
- Severity: Critical (CVSS 9.1)
- Affected: Gladinet Triofox
- Attack Vector: Network / HTTP Management Interface
This vulnerability allowed attackers to bypass access controls by manipulating HTTP Host headers, granting access to administrative setup workflows. Attackers created administrator accounts without credentials and leveraged built-in maintenance features to execute code as SYSTEM.
The delayed public disclosure meant many organizations remained exposed long after patches were available, emphasizing the importance of proactive patching even in the absence of public CVE details.
CVE-2025-5086 – DELMIA Apriso Deserialization RCE
- Severity: Critical (CVSS 9.0)
- Affected: DELMIA Apriso (2020–2025)
- Attack Vector: Network / HTTP SOAP Requests
Unsafe deserialization in Apriso’s SOAP services allowed unauthenticated attackers to deploy malware directly into manufacturing environments. Exploitation blurred the line between IT and OT compromise, enabling espionage, production disruption, and intellectual property theft.
Given Apriso’s role in production scheduling and quality management, successful attacks posed serious risks to industrial continuity.
CVE-2025-53690 – Sitecore ViewState Deserialization RCE
- Severity: Critical (CVSS 9.0)
- Affected: Sitecore Experience Manager / Platform
- Attack Vector: Network / Web Application (ViewState)
Attackers exploited legacy machine keys published in old Sitecore deployment guides to abuse insecure ViewState deserialization. Once compromised, attackers gained full web server control and pivoted into internal networks.
The vulnerability highlighted how outdated documentation and insecure defaults can create long-term security debt.
CVE-2025-62221 – Windows Cloud Files Driver Privilege Escalation
- Severity: High (CVSS 7.8)
- Affected: Windows Cloud Files Mini Filter Driver
- Attack Vector: Local System Access (Authenticated)
This use-after-free vulnerability allowed attackers to escalate privileges to SYSTEM after initial compromise. Because the driver is present by default, exploitation was possible even on systems without cloud storage clients installed.
Attackers frequently used this flaw to disable security tooling and establish persistent high-privilege access.
CVE-2025-62215 – Windows Kernel Race Condition
- Severity: High (CVSS 7.0)
- Affected: Windows Kernel (All supported versions)
- Attack Vector: Local System Access (Authenticated)
A race condition leading to double-free heap corruption enabled attackers to gain SYSTEM privileges. The vulnerability was commonly used in post-exploitation phases following phishing or RCE attacks.
It reinforced the continued importance of kernel hardening and behavior-based detection.
CVE-2025-48572 – Android Framework Privilege Escalation
- Severity: High
- Affected: Android Framework (Android 13–16)
- Attack Vector: Mobile Application (Malicious App)
This vulnerability allowed malicious applications to bypass background execution restrictions, enabling stealthy privilege escalation without user interaction. It was primarily observed in targeted surveillance campaigns.
CVE-2025-48633 – Android Framework Information Disclosure
- Severity: High
- Affected: Android Framework (Android 13–16)
- Attack Vector: Mobile Application / Sandbox Bypass
A logic flaw in system services enabled access to sensitive memory and system data. When chained with privilege escalation vulnerabilities, attackers achieved full device compromise.
CVE-2025-6218 – WinRAR Path Traversal
- Severity: High (CVSS 7.8)
- Affected: WinRAR 7.11 and earlier
- Attack Vector: User Interaction (Malicious Archive)
Malicious archives exploited path traversal flaws to write files outside extraction directories, including startup folders. The vulnerability was widely used in phishing campaigns by APT groups.
CVE-2025-48384 – Git Arbitrary File Write
- Severity: High (CVSS 8.0–8.1)
- Affected: Git on macOS and Linux
- Attack Vector: Network / Malicious Git Repository Clone
This vulnerability targeted developer environments by exploiting inconsistencies in carriage return handling. Attackers wrote malicious files during recursive clones, executing code via Git hooks and enabling supply-chain compromise.
Final Thoughts
The most exploited CVEs of 2025 clearly demonstrate how rapidly the threat landscape is evolving and how quickly attackers are able to operationalize newly disclosed vulnerabilities. From unauthenticated remote code execution in widely used web frameworks to privilege escalation flaws in operating systems and VPN appliances, these vulnerabilities highlight systemic weaknesses across both modern and legacy technologies.
One of the most concerning trends is the speed of exploitation. In several cases, proof-of-concept exploits appeared within hours of public disclosure, leaving organizations with an extremely narrow window to respond. This reinforces the reality that traditional, slow patch cycles are no longer sufficient for internet-facing systems and critical infrastructure.
Another key takeaway is the continued attractiveness of perimeter devices and core services as targets. VPN gateways, firewalls, update servers, and identity-adjacent components remain prime entry points for both financially motivated threat groups and state-sponsored actors. Once compromised, these systems provide attackers with deep network visibility and long-term persistence.
To mitigate these risks, organizations must treat vulnerability management as a continuous and strategic function rather than a periodic maintenance task. Prioritizing patches based on active exploitation, closely monitoring CISA’s Known Exploited Vulnerabilities catalog, and improving detection for post-exploitation behavior are now essential baseline practices.
As we move into 2026, the lessons from 2025 are clear: assume rapid exploitation, reduce exposure wherever possible, and focus defensive efforts on the vulnerabilities that attackers are actively using—not just the ones with high CVSS scores. Continuous vigilance, timely patching, and layered defenses remain the most effective way to stay ahead of an increasingly aggressive threat landscape.
