Top Web Application Vulnerabilities We Still Find in 2026

Some vulnerabilities never go away. Despite decades of developer education, a robust ecosystem of SAST and DAST tools, and the OWASP Top 10 being published since 2003, security assessments in 2026 routinely uncover the same classes of vulnerabilities — sometimes in exactly the ways they were found fifteen years ago. This is not a commentary on developer negligence; it reflects the complexity of modern web applications, the pace of delivery, and the technical debt that accumulates in every product at scale. Here are the vulnerability classes CyVigilant testers find most consistently across web application assessments.

1. Broken Access Control (OWASP A01:2021)

Broken access control topped the OWASP Top 10 in 2021 and remains the most common high-severity finding in web application assessments. The root cause is almost always the same: authorisation logic is implemented inconsistently across the application, often added reactively rather than architecturally. Specific manifestations include: forced browsing to restricted pages by manipulating URLs, IDOR vulnerabilities where user-supplied IDs are not validated against ownership, horizontal privilege escalation via API endpoints that enforce authentication but not object-level authorisation, and missing authorisation on administrative functions accessible by guessing URLs or API paths.

CWE-284 (Improper Access Control) is the underlying weakness. In the BFSI context, IDOR vulnerabilities in customer account APIs are among the most serious findings we report — they directly enable unauthorised access to financial data. Remediation requires architectural enforcement of authorisation at the service layer, not just at the UI.

2. Injection — SQL, NoSQL, and Command Injection

Injection vulnerabilities (OWASP A03:2021) persist because they arise from a fundamental pattern: user-supplied data being incorporated into interpreted commands or queries without adequate separation. SQL injection remains present in legacy code, in frameworks where developers use string concatenation instead of parameterised queries, and in third-party libraries that are not regularly audited. NoSQL injection is under-recognised in MongoDB and similar databases where query operators like `$where` and direct JSON injection are possible. Command injection appears frequently in administrative functions that shell out to system commands.

Modern ORM frameworks reduce but do not eliminate SQL injection — raw query methods are still used in performance-sensitive paths, and developers sometimes bypass the ORM for complex queries. SAST tools catch many injection patterns, but dynamic testing against a running application finds injection vulnerabilities that static analysis misses because the vulnerable path depends on runtime state.

3. Cryptographic Failures (OWASP A02:2021)

Cryptographic failures are a broad category that covers weak encryption, improper key management, missing encryption, and protocol weaknesses. Common findings in 2026 include: sensitive data (passwords, PII, financial data) stored in plaintext or with weak hashing (MD5, SHA-1 without salting); TLS misconfiguration allowing weak cipher suites or TLS 1.0/1.1 connections; JWT tokens signed with weak secrets or stored insecurely in localStorage where they are accessible to JavaScript; and session tokens that fail randomness requirements, enabling session prediction attacks.

For applications subject to the DPDP Act 2023 or PCI-DSS, cryptographic failures involving personal or payment card data carry significant regulatory risk in addition to the security impact. The CWE-327 (Use of a Broken or Risky Cryptographic Algorithm) class of findings requires remediation even when the immediate exploitability is not obvious.

4. Security Misconfiguration (OWASP A05:2021)

Security misconfiguration findings range from low-risk (verbose error pages exposing framework versions) to critical (publicly accessible cloud storage containing customer data, unrestricted administrative interfaces accessible without VPN, or debug endpoints left enabled in production). Common examples across recent assessments: cloud storage buckets with public read access containing customer exports; administrative panels for CMS or monitoring tools accessible on the public internet with default or weak credentials; HTTP security headers absent or misconfigured (missing Content-Security-Policy, X-Frame-Options, or HSTS); and CORS policies configured to allow any origin (`Access-Control-Allow-Origin: *`) on authenticated endpoints.

5. Vulnerable and Outdated Components (OWASP A06:2021)

Dependency management has improved with the widespread adoption of software composition analysis (SCA) tools, but outdated and vulnerable third-party libraries remain a persistent finding. The challenge is not just identifying vulnerable components — it is the gap between identification and remediation. Organisations typically know they have vulnerable dependencies; the prioritisation and remediation process is where the lag occurs. Critical and high-severity CVEs in widely used libraries (Log4Shell in 2021 being the canonical example) require immediate response. The challenge is that most production environments have hundreds of transitive dependencies, and each update carries regression risk.

The CERT-In Directions of April 2022 establish explicit vulnerability management SLAs: critical vulnerabilities must be patched or mitigated within 6 hours for certain incident categories, and organisations are required to report significant vulnerabilities. For web applications, SLA-driven patching of critical and high CVEs in production dependencies is both a security requirement and a regulatory obligation for CERT-In regulated entities.

What this means for your testing programme

The persistence of these vulnerability classes reflects that security is an ongoing programme, not a one-time project. Annual VAPT catches these issues when they accumulate. More frequent testing — quarterly assessments of high-risk applications, automated DAST in CI/CD for continuous coverage — reduces the window between introduction and detection. The combination of a rigorous VAPT by expert testers and automated tooling is the most cost-effective approach for maintaining a secure baseline.

CyVigilant's web application VAPT covers the full OWASP Top 10 and ASVS with manual testing depth that goes beyond automated scanners. For a high-value application, consider coupling VAPT with a secure code review to address vulnerabilities at the source. Talk to an expert to design a testing programme appropriate to your application's risk profile.