Is CVE-2026-118516 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-118516 being exploited in the wild.

How severe is CVE-2026-118516?

Informational severity, published 4 November 2026.

Which products and versions are affected?

Symfony Routing prior to 5.4.56, 6.x prior to 6.4.50, 7.x prior to 7.4.23, 8.x prior to 8.1.11.

How is CVE-2026-118516 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-118516?

Check whether you run Symfony Routing at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-118516: Symfony Routing host-path interpretation bypass in UrlMatcher

CVE-2026-118516 · Severity: info · Published 2026-11-04

Symfony Routing's UrlMatcher and CompiledUrlMatcher components handle host and path matching differently, allowing attackers to craft requests that bypass path-based access control rules. An attacker can manipulate the Host header to make a request appear to match a different route than intended, potentially reaching protected controllers without proper authentication or authorization checks.

Vendors: Symfony.

Quick answers

Is CVE-2026-118516 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-118516 being exploited in the wild.
How severe is CVE-2026-118516?: Informational severity, published 4 November 2026.
Which products and versions are affected?: Symfony Routing prior to 5.4.56, 6.x prior to 6.4.50, 7.x prior to 7.4.23, 8.x prior to 8.1.11.
Is there a fix for CVE-2026-118516?: Yes: fixed in Symfony Routing 5.4.56, 6.4.50, 7.4.23, 8.1.11. Until then: Ensure framework.trusted_hosts is properly configured to reject unexpected Host headers; however, applications using host placeholders with broad matching patterns like .+ may remain vulnerable and require upgrading. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-118516 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-118516?: Check whether you run Symfony Routing at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

Fixed in: Symfony Routing 5.4.56, 6.4.50, 7.4.23, 8.1.11

Ensure framework.trusted_hosts is properly configured to reject unexpected Host headers; however, applications using host placeholders with broad matching patterns like .+ may remain vulnerable and require upgrading.

Technical details

CompiledUrlMatcher matches host and path as a combined string, while UrlMatcher matches them separately. A host placeholder can match "/" and consume part of the path, routing the request differently than UrlMatcher would interpret it. Path-based authorization rules (access_control, firewall patterns) are evaluated against the actual request path and do not apply if the routing logic bypasses them, allowing unauthenticated access to protected endpoints. The vulnerability requires routes with host placeholders protected by path-based rules.

Affected products

Symfony Routing prior to 5.4.56, 6.x prior to 6.4.50, 7.x prior to 7.4.23, 8.x prior to 8.1.11

Timeline

2026-11-04: disclosed

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