symfony: Insufficient Verification of Data Authenticity
CVE-2026-45069 is a critical-severity insufficient verification of data authenticity vulnerability in symfony, with a CVSS 3.1 base score of 9.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected symfony versions: >= 6.3.0, < 6.4.40; >= 7.4.0, < 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 0.26% chance of exploitation within 30 days, which is low compared with other CVEs.
Critical severity: a successful attack would have severe impact.
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 | >= 6.3.0, < 6.4.40; >= 7.4.0, < 7.4.12; >= 8.0.0-BETA1, < 8.0.12 | Not stated |
| Symfony | security-http | >= 6.3.0, < 6.4.40; >= 7.4.0, < 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
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 8.8 | High | CNA (github.com) |
| CVSS 3.1 | 9.1 | Critical | NVD |
Official description
Symfony is a PHP framework for web and console applications and a set of reusable PHP components. Prior to 6.4.40, 7.4.12, and 8.0.12, OidcTokenHandler::verifyClaims() registered audience (aud), issuer (iss), and expiry (exp) checkers but did not pass the mandatory claims list to ClaimCheckerManager::check(), so a validly signed JWT that omitted those claims could pass verification. This issue is fixed in versions 6.4.40, 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: Insufficient Verification of Data Authenticity
The product does not sufficiently verify the origin or authenticity of data, in a way that causes it to accept invalid data.
More Insufficient Verification of Data Authenticity vulnerabilities (CWE-345)
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/releases/tag/v6.4.40Product, Release Notes
- 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 Insufficient Verification of Data Authenticity vulnerabilities
- 8.2 High severity
- 8.3 High severity
- 7.4 High severity
- 9.9 Critical severity
- 8.8 High severity
- 8.1 High severity
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