PHP2Shell : See if you’re affected with a free external attack surface scan. Click Here > 

Back
New CVE Detected

CVE-2026-57577 – Denial of Service (ReDoS) – DotVVM Routing (versions before 4.2.11, 4.3.0–4.3.14, 5

Be the first to know when new zero-days emerge:

Subscribe to Email Alerts
Subscribe to RSS Feed

Summary

CVE-2026-57577 is a Regular Expression Denial of Service (ReDoS) vulnerability in DotVVM, an open-source MVVM framework for building web applications on .NET. Applications that define routes with multiple unconstrained parameters in a single path segment are vulnerable to catastrophic regex backtracking in the route-matching engine, allowing a remote, unauthenticated attacker to exhaust server CPU resources. The issue has a CVSS score of 8.2 (High).

Technical details

  • Root cause: DotvvmRouteParser.RouteRegex, used internally by DotvvmRoute.IsMatch, previously had no matching timeout, so pathological input could drive the .NET regex engine into excessive backtracking.
  • Trigger conditions: the application must define a route containing multiple unconstrained parameters within a single path segment without a literal separator (e.g. a pattern like edit/{a}-{b}-{c}/done).
  • Attack vector: network — an attacker sends a specially crafted, long, "near-match" URL path (e.g. thousands of dash characters) to the vulnerable route.
  • Impact: excessive CPU consumption during route matching, leading to service degradation or denial of service; no confidentiality or integrity impact.

Affected software

  • DotVVM versions prior to 4.2.11
  • DotVVM 4.3.0 up to (but not including) 4.3.15
  • DotVVM 5.0.0-preview01 up to (but not including) 5.0.0-preview09-final

Severity

CVSS score: 8.2 (High)
Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Mitigation and recommended actions

  • Immediate: upgrade to DotVVM 4.2.11, 4.3.15, or 5.0.0-preview09-final (or later), which apply a one-second timeout to route-matching regex operations and fall back to the .NET non-backtracking regex engine (on .NET 8.0+) or return HTTP 503 when the timeout is exceeded.
  • If immediate patching is not possible:
    • Add explicit constraints to route parameters (e.g. {param:alpha}) to eliminate character-type ambiguity.
    • Use regex constraints such as {param:regex([^-]*)} to exclude problematic separator characters from matching.
    • Separate multiple route parameters with literal path separators (/) rather than placing them adjacently in a single segment.

References

Are you exposed?

Get a free report of your organization’s exposure to this CVE and threat

  • Mapping of all Assets with this Technology
  • Identification of potentially exposed assets to this CVE
  • Confirmation of verified exploitable assets
Get Exposure Report

How IONIX’s External Exposure Management Platform Detects and Validates
Zero-Days to Shrink MTTR

1

Map your entire attack surface (continously)

IONIX uses multi-factor discovery methods, including DNS analysis, certificate mapping, metadata inspection, and more, to automatically map every internet-facing asset across your environment. This includes cloud instances, third-party platforms, shadow IT, and even forgotten infrastructure that traditional tools miss.

2

Monitor for new CVEs

Dozens of threat intel feeds using agentic technology are continuously analyzed to detect the appearance of proof-of-concept code, exploit kits, and indicators of active targeting. IONIX goes further by applying AI to proactively evaluate whether emerging vulnerabilities are likely to be exploited, even before PoCs go public.

3

Identify Potential External Exposures

Not all CVEs matter. IONIX filters vulnerabilities by asking attacker-centric questions: Can it be reached from the internet? Does it require authentication? Is it being exploited in the wild? This dramatically reduces noise and focuses teams on threats that can actually be weaponized.

4

Create Safe, Scalable Exploit Validations

IONIX transforms real-world PoCs into safe, non-intrusive test payloads that can be run in production environments without disruption. These simulations are precisely targeted to the systems that are vulnerable, ensuring rapid validation without unnecessary load.

5

Execute Exploit Validations

By combining context about software stack, versioning, exposure status, and reachability, IONIX ensures that only the right payloads are executed against the right assets, maximizing efficiency and minimizing risk.

6

Drive Fast and Actionable Remediation

Results are routed through integrations with ticketing, SOAR, and SIEM tools. Issues are written in plain language, bundled into remediation clusters, and prioritized based on asset criticality, exploitability, and blast radius. This shortens mean time to remediation (MTTR) and empowers teams to act with confidence.

Are you exposed?

Get a free report of your organization’s exposure to this CVE and threat

  • Mapping of all Assets with this Technology
  • Identification of potentially exposed assets to this CVE
  • Confirmation of verified exploitable assets
Get Exposure Report
Close

Subscribe to Threat Center RSS

Copy/paste the link below into your preferred RSS reader or follow these instructions to subscribe to Slack alerts.

Open RSS feedSlack setup instructions

Close

Get Real-Time CVE Alerts to Your Email

Be the first to know when new zero-days emerge