symfony: Uncontrolled Resource Consumption
CVE-2026-45756 is a high-severity uncontrolled resource consumption vulnerability in symfony, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected symfony versions: >= 7.3.0-BETA1, < 7.4.12; >= 8.0.0-BETA1, < 8.0.12. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.63% chance of exploitation within 30 days, higher than 51% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of symfony you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Symfony | symfony | >= 7.3.0-BETA1, < 7.4.12; >= 8.0.0-BETA1, < 8.0.12 | Not stated |
| Symfony | json-path | >= 7.3.0-BETA1, < 7.4.12; >= 8.0.0-BETA1, < 8.0.12 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 8.2 | High | CNA (github.com) |
| CVSS 3.1 | 7.5 | High | NVD |
Official description
Symfony is a PHP framework for web and console applications and a set of reusable PHP components. From 7.3.0-BETA1 until 7.4.12 and 8.0.12, the JsonPath component compiles attacker-controlled match() and search() filter patterns directly into preg_match() without a length cap, i-regexp restriction, or bounded backtracking, allowing catastrophic-backtracking expressions to pin worker CPU and cause denial of service. This issue is fixed in versions 7.4.12 and 8.0.12.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Uncontrolled Resource Consumption
The product does not properly control the allocation and maintenance of a limited resource.
How developers prevent this class of flaw
- Ensure that protocols have specific limits of scale placed on them.
- Ensure that all failures in resource allocation place the system into a safe posture.
More Uncontrolled Resource Consumption vulnerabilities (CWE-400)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- github.com/symfony/symfony/commit/1ac2d47418ec23066112db1e6ca35be6fe123d14
- github.com/symfony/symfony/releases/tag/v7.4.12Product, Release Notes
- github.com/symfony/symfony/releases/tag/v8.0.12Product, Release Notes
Other vulnerabilities in symfony
- 8.6 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 9.8 Critical severity
- 7.5 High severity
Recent Uncontrolled Resource Consumption vulnerabilities
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
Spotted an error? Tell us.