As everyone involved in software development knows, code must be both functional and secure. Too often, software security vulnerabilities hide behind perfectly working features, turning seemingly stable applications into ticking time bombs. When overlooked, these software vulnerabilities can become entry points for hackers, leading to data leaks, service disruptions, or full-scale cybersecurity incidents.
Here, we’ve identified the most common security vulnerabilities. We’ll explore the threats that compromise functionality and expose sensitive data, and show you how to prevent them from ever making it into production.
Code security flaws are liabilities with real consequences. A single vulnerability can serve as an entry point for attackers, resulting in unauthorized access, data breaches, and security incidents. And the impact isn’t just felt by IT teams: Leaked credentials, stolen data, and compromised systems affect customers, partners, and your brand’s credibility.
And cyberattacks aren’t the only risk. In some situations, poor application security can trigger regulatory action under frameworks like GDPR, HIPAA, and PCI DSS. For many organizations, the costs of non-compliance can be just as damaging as the breach.
The vulnerabilities below are among the most frequently exploited in data breaches and represent some of the most pressing security issues developers face. Many map to the OWASP Top 10 and are directly associated with identifiers in the Common Weakness Enumeration (CWE) and Common Vulnerabilities and Exposures (CVE) databases.
SQL Injection (SQLi) remains one of the most widely exploited software vulnerabilities. It’s dangerous because it often enables attackers to extract confidential information, escalate privileges, or gain full administrative control, especially in systems lacking proper input validation and privilege controls.
Despite widespread awareness, SQL injection is still common in 2025 due to legacy codebases, insecure development practices, and inconsistent input validation in many web applications.
A recent example is the MOVEit Transfer breach in May 2023. Attackers exploited a zero-day SQL injection vulnerability in this widely used file transfer application, allowing them to install a custom web shell and exfiltrate data from thousands of organizations worldwide.
PreparedStatement stmt = conn.prepareStatement(“SELECT * FROM users WHERE email = ?”);
stmt.setString(1, userInput);
Cross-site scripting (XSS) occurs when an attacker injects malicious JavaScript into a web page, which then executes in another user’s browser. It’s used to impersonate users, deliver malware, or exploit browser extensions. XSS typically targets web apps that fail to properly handle user input in HTML or JavaScript contexts. This can lead to session hijacking, cookie theft, user redirection, or a spoofed interface that appears to come from a trusted source.
In early 2025, attackers exploited an XSS vulnerability in the Krpano framework, which is a tool used for embedding images and creating virtual tours. The exploit led to the injection of malicious scripts into hundreds of websites, manipulating search engine results and sending out spam advertisements.
Broken access control occurs when an application fails to properly enforce restrictions on what authenticated users are allowed to do. These flaws can result in unauthorized access to data, actions, or system functionality. They often stem from misconfigured permissions, missing authorization logic, or predictable object references (e.g., userId=123 in a URL). Common examples include:
A data breach involving broken access control occurred in October 2023, affecting Atlassian’s Confluence Data Center and Server products. The vulnerability, identified as CVE-2023-22515, allowed attackers to create administrator accounts on publicly accessible Confluence instances that gave them full administrative access without authentication.
Security misconfiguration occurs when applications, servers, or infrastructure are set up with overly permissive or insecure defaults that widen your attack surface, offering attackers easy entry without needing to get into the code. Common examples include exposed admin panels, default credentials, error messages, unsecured cloud storage, and unnecessary services.
A notable example of a data breach caused by security misconfiguration occurred in September 2023 when Microsoft disclosed a massive data leak involving 38 terabytes of internal data. The breach was attributed to a misconfigured Azure Blob Storage container, which inadvertently exposed sensitive information, including employee credentials and internal messages.
As apps become increasingly API-first, insecure endpoints can serve as backdoors to otherwise protected systems, leading to unauthorized access, data leaks, or service disruption. APIs are prime targets for attackers due to their access to large volumes of sensitive information, lack of documentation, and reliance on open-source components with known vulnerabilities.
In April 2024, vulnerabilities in PandaBuy’s API resulted in data theft that affected 1.3 million users. This breach underscores the importance of API access controls to thwart attempts at unauthorized access.
Insecure design refers to flaws in an application’s architecture, logic, or workflows that introduce security risks even if the underlying code is written correctly. Unlike injection or misconfiguration vulnerabilities, insecure design stems from a lack of threat modeling, failure to define security requirements, or neglect of abuse cases during the planning phase. Examples include:
One of the most prominent instances of a breach stemming from insecure design is the 2017 Equifax data breach, which exposed the personal information of 147 million people. While the breach was initially attributed to an unpatched vulnerability, the underlying issues and lack of layered defenses, access controls, and effective monitoring reflects an insecure design where security considerations were not integral to the system’s planning.
This category covers flaws in how users are identified and authenticated, such as weak login mechanisms, missing multi-factor authentication (MFA), exposed session tokens, or poor password policies. These failures frequently lead to credential stuffing, brute-force attacks, or session hijacking.
In 2024, hackers accessed data from over 100 customers of Snowflake, Inc. by leveraging login credentials obtained from infostealers to access Snowflake cloud accounts using only a username and password. The absence of MFA allowed the attackers to infiltrate these accounts, highlighting a failure in authentication controls.
Software and data integrity failures occur when code, configuration, or update mechanisms are susceptible to tampering. These vulnerabilities are part of supply chain attacks where trust in open-source packages, CI/CD workflows, or updates is exploited. Examples include insecure package downloads, unverified third-party dependencies, or unsigned updates that are deployed regardless.
In February 2024, Change Healthcare experienced a ransomware attack stemming from a software and data integrity failure that involved the compromise of critical healthcare infrastructure through the exploitation of software vulnerabilities. This breach impacted over 100 million patients’ personal data and caused significant disruptions in healthcare operations.
How to prevent or detect it:
Security logging and monitoring failures occur when applications don’t generate, store, or surface security-relevant events, which makes it difficult to detect and respond to breaches. These failures don’t stop there, as they can also lead to non-compliance with standards like SOC 2, HIPAA, and PCI DSS, which require visibility into anomalies and system activity.
Common issues include:
In September 2024, Infosys McCamish Systems disclosed a significant data breach that affected up to 6.5 million records. The breach occurred between October and November 2023 but was not detected until months later. The delayed detection of the breach suggests deficiencies in their logging and monitoring practices, which should have caught the issue.
Cryptographic failures or “sensitive data exposure” occur when sensitive data isn’t properly protected in transit or at rest. It differs from missing encryption in that these issues usually stem from how cryptography is applied, managed, or integrated. Common examples include using broken or outdated algorithms like SHA-1 or MD5 for hashing passwords, storing API tokens in plain text, or hardcoding cryptographic keys directly into source code.
In October 2023, genetic testing company 23andMe experienced a data breach affecting nearly 7 million users. Attackers leveraged credential stuffing techniques to gain unauthorized access to user accounts, exploiting the lack of multi-factor authentication and inadequate encryption of sensitive genetic data.
This vulnerability occurs when applications depend on third-party libraries, frameworks, or packages with known vulnerabilities due to age, neglect, or missing patches. These components may have been technically sound at one time, but security issues emerged and now any project that continues to use them inherits those risks.
Between October 16 and 19, 2023, attackers exploited a vulnerability in Citrix’s software, known as “Citrix Bleed,” to gain unauthorized access to Xfinity’s internal systems. This breach exposed personal information of 35+ million customers, including usernames, hashed passwords, and, for some, Social Security numbers and birthdates.
Server-side request forgery (SSRF) happens when an attacker tricks a server into making unauthorized HTTP requests (often to internal services) by submitting a malicious or user-controlled URL. This vulnerability turns a server into a proxy, allowing attackers to reach internal-only endpoints or cloud metadata APIs.
Unlike broader API flaws, SSRF is network-oriented. It exploits the trust that backend systems place in each other, not in external callers.
In 2019, Capital One experienced a data breach affecting approximately 106 million individuals in the United States and Canada. The breach was facilitated by an SSRF vulnerability in a misconfigured Web Application Firewall (WAF), which allowed attackers to query AWS metadata endpoints and escalate privileges.
Cross-site request forgery (CSRF) tricks an authenticated user’s browser into performing unintended actions on a web app. The app treats the request as legitimate because it includes valid session cookies automatically sent by the browser (even if the user never intended to make the request). For example, a logged-in user visiting a malicious page could unknowingly trigger a funds transfer or account update if protections aren’t in place.
Unlike XSS, which runs malicious code inside the browser, CSRF abuses the browser itself to submit legitimate-looking requests without the user’s intent. It’s especially harmful in apps using cookie-based auth without anti-CSRF tokens, SameSite protections, or safeguards on sensitive GET/POST actions.
In 2022, a CSRF vulnerability was discovered in Google Cloud Shell’s file upload API, allowing attackers to upload malicious files, such as a .bash_profile, to a user’s environment. This file would execute every time the user initiated a shell session, potentially leading to unauthorized command execution and compromising the user’s environment.
Improper input validation occurs when application security fails to enforce rules on user input, such as type, length, format, or allowed values. It’s one of the root causes behind other application security issues like SQL injection, cross-site scripting, buffer overflows, and command injection. And because input validation happens early in the data flow, it is a first line of defense for blocking malicious input before it can reach vulnerable components.
The Atlassian Confluence vulnerability mentioned above is a good example of how a single exploit can stem from multiple root causes and fall into more than one vulnerability category. In addition to being an example of broken access control, it also fits improper input validation because the exploit depended on manipulating HTTP requests and poorly validated input— which should have been caught by proper input handling.
Directory traversal occurs when an attacker manipulates file paths to access files or directories outside the intended scope. Unrestricted URLs, often tied to Insecure Direct Object References (IDOR), allow attackers to access resources by modifying URL parameters without proper authorization. Directory traversal can expose sensitive files like logs, configuration files, or password hashes. IDOR vulnerabilities can let attackers view or alter other users’ data simply by guessing or iterating resource identifiers.
A recent instance of a directory traversal vulnerability is CVE-2017-12637 in SAP NetWeaver Application Server Java. This flaw allowed attackers to access files on the server by manipulating URL paths, potentially exposing sensitive configuration files and other data.
Insecure deserialization is when an application accepts serialized data like JSON, XML, or binary objects and converts it into code or objects without proper validation. If an attacker modifies that data, they can inject malicious code, escalate privileges, or trigger remote code execution during deserialization.
Because serialization is used behind the scenes in many frameworks, insecure deserialization is often overlooked—yet it remains one of the most powerful and dangerous software security vulnerabilities.
In July 2024, a critical vulnerability was identified in the Progress Telerik Report Server. This flaw stemmed from insecure deserialization, allowing attackers to execute arbitrary code on the server by sending serialized objects. It required no authentication, so attackers could exploit it without valid credentials to gain full control over the affected server.
Buffer overflows occur when a program writes more data to a fixed-size memory buffer than it can accommodate, causing that data to spill into adjacent memory. This can overwrite variables, corrupt return addresses, or disrupt control flow. The issue is especially common in low-level languages like C and C++, which lack built-in memory safety features.
While often considered an “old-school” vulnerability, buffer overflows remain a real threat, especially in embedded systems, firmware, and legacy code. They can lead to remote code execution, crashes, or full system compromise when exploited, potentially allowing attackers to take full control of the system.
In December 2022, Fortinet disclosed a critical heap-based buffer overflow vulnerability in its FortiOS SSL-VPN component, identified as CVE-2022-42475. This flaw allowed unauthenticated remote attackers to execute arbitrary code or commands.
DevOps artifacts like .env files, Dockerfiles, build logs, .git directories, and CI/CD secrets are critical during development but dangerous if left exposed. They often result from misconfigured cloud storage, careless Git commits, or overlooked build artifacts. When these files make it into production, they can leak credentials, API keys, or service configurations. Even worse, when sensitive credentials or secrets are exposed, compliance violations under frameworks like SOC 2, HIPAA, GDPR, or PCI DSS can result.
In August 2024, a vulnerability dubbed “ArtiPACKED” was discovered in GitHub Actions artifacts. This flaw could be exploited to take over repositories and gain access to organizations’ cloud environments.
The following vulnerabilities often appear in penetration tests and secure code reviews. Some exploit nuanced behaviors, while others target overlooked client-side risks.
Every vulnerability you prevent in development is one less risk you face in production. That’s why security testing starts with the code itself. By scanning early and often, static analysis makes it easy to detect and resolve security flaws before they reach users, auditors, or attackers.
With support for 30+ programming languages, Kiuwan offers built-in detection for the most common and dangerous vulnerabilities, including those from the OWASP Top 10, CWE, and even known CVEs. And beyond detection, Kiuwan provides context-specific remediation guidance that tells you what’s wrong and how to fix it.
Request a free demo today to see how Kiuwan’s security tools can help you detect and fix vulnerabilities so you can ship safer code.
