symfony: Interpretation Conflict
CVE-2026-47767 is a critical-severity interpretation conflict vulnerability in symfony, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected symfony versions: >= 5.4.46, < 5.4.52; >= 6.4.14, < 6.4.40; >= 7.1.7, < 7.4.12, and others listed below. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.72% chance of exploitation within 30 days, higher than 55% of scored 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 | >= 5.4.46, < 5.4.52; >= 6.4.14, < 6.4.40; >= 7.1.7, < 7.4.12; >= 8.0.0-BETA1, < 8.0.12 | Not stated |
| Symfony | runtime | >= 5.4.46, < 5.4.52; >= 6.4.14, < 6.4.40; >= 7.1.7, < 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
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 8.3 | High | CNA (github.com) |
| CVSS 3.1 | 9.8 | Critical | NVD |
Official description
Symfony is a PHP framework for web and console applications and a set of reusable PHP components. From 5.4.46 until 5.4.52, 6.4.40, 7.4.12, and 8.0.12, the CVE-2024-50340 fix gated runtime argv parsing on empty($_GET), but parse_str() and the web SAPI can disagree, allowing a crafted query string to leave $_GET empty while $_SERVER['argv'] still carries attacker-controlled --env or --no-debug flags that change APP_ENV or APP_DEBUG. This issue is fixed in versions 5.4.52, 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: Interpretation Conflict
Product A handles inputs or steps differently than Product B, which causes A to perform incorrect actions based on its perception of B's state.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Patches and release notes
- github.com/symfony/symfony/commit/3228c3806ee511008bea19a95084d460b17e5d25
- github.com/symfony/symfony/releases/tag/v5.4.52Product, 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
- 7.5 High severity
- 7.5 High severity
Recent Interpretation Conflict vulnerabilities
- 9.1 Critical severity
- 7.5 High severity
- 7.5 High severity
- 9.8 Critical severity
- 7.5 High severity
- 9.1 Critical severity
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