UBUNTU-CVE-2026-45305
A vulnerability in Symfony PHP framework versions prior to 5.4.52, 6.4.40, 7.4.12, and 8.0.12 allows crafted YAML input to cause the parser to hang indefinitely due to overlapping quantifiers in regular expressions used in the cleanup() function. This denial-of-service condition is fixed in the specified patched versions.
AI Analysis
Technical Summary
The Symfony PHP framework's Yaml component had a flaw in the Parser::cleanup() method where regular expressions with overlapping quantifiers were used to clean YAML directives, comments, and document markers. This flaw allowed specially crafted input to cause the parser to hang for an arbitrarily long time, effectively a denial-of-service vulnerability. The issue affects multiple Symfony versions prior to 5.4.52, 6.4.40, 7.4.12, and 8.0.12, which include the versions packaged in various Ubuntu releases. The vulnerability is resolved in these fixed versions.
Potential Impact
An attacker can supply malicious YAML input that causes the Symfony YAML parser to hang indefinitely, leading to a denial-of-service condition. This can disrupt applications relying on YAML parsing, potentially impacting availability. There is no indication of privilege escalation, code execution, or data disclosure from this vulnerability.
Mitigation Recommendations
A fix is available in Symfony versions 5.4.52, 6.4.40, 7.4.12, and 8.0.12. Users should upgrade to these or later versions to remediate the vulnerability. Since this is not a cloud service, manual patching or upgrading is required. Patch status is confirmed by the vendor advisory.
UBUNTU-CVE-2026-45305
Description
A vulnerability in Symfony PHP framework versions prior to 5.4.52, 6.4.40, 7.4.12, and 8.0.12 allows crafted YAML input to cause the parser to hang indefinitely due to overlapping quantifiers in regular expressions used in the cleanup() function. This denial-of-service condition is fixed in the specified patched versions.
CVSS v4.0
Affected software
pkg:deb/ubuntu/[email protected]?arch=source&distro=xenialpkg:deb/ubuntu/[email protected]+dfsg-1ubuntu0.1+esm2?arch=source&distro=esm-apps/bionicpkg:deb/ubuntu/[email protected]+dfsg-1ubuntu1+esm2?arch=source&distro=esm-apps/focalpkg:deb/ubuntu/[email protected]+dfsg-1ubuntu8+esm1?arch=source&distro=esm-apps/jammypkg:deb/ubuntu/[email protected]+dfsg-3ubuntu3+esm1?arch=source&distro=esm-apps/noblepkg:deb/ubuntu/[email protected]+dfsg-1?arch=source&distro=questingpkg:deb/ubuntu/[email protected]+dfsg-1ubuntu1?arch=source&distro=resoluteRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The Symfony PHP framework's Yaml component had a flaw in the Parser::cleanup() method where regular expressions with overlapping quantifiers were used to clean YAML directives, comments, and document markers. This flaw allowed specially crafted input to cause the parser to hang for an arbitrarily long time, effectively a denial-of-service vulnerability. The issue affects multiple Symfony versions prior to 5.4.52, 6.4.40, 7.4.12, and 8.0.12, which include the versions packaged in various Ubuntu releases. The vulnerability is resolved in these fixed versions.
Potential Impact
An attacker can supply malicious YAML input that causes the Symfony YAML parser to hang indefinitely, leading to a denial-of-service condition. This can disrupt applications relying on YAML parsing, potentially impacting availability. There is no indication of privilege escalation, code execution, or data disclosure from this vulnerability.
Mitigation Recommendations
A fix is available in Symfony versions 5.4.52, 6.4.40, 7.4.12, and 8.0.12. Users should upgrade to these or later versions to remediate the vulnerability. Since this is not a cloud service, manual patching or upgrading is required. Patch status is confirmed by the vendor advisory.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- UBUNTU-CVE-2026-45305
- Osv Schema Version
- 1.7.0
- Aliases
- []
- Ecosystems
- ["Ubuntu:16.04:LTS","Ubuntu:Pro:18.04:LTS","Ubuntu:Pro:20.04:LTS","Ubuntu:Pro:22.04:LTS","Ubuntu:Pro:24.04:LTS","Ubuntu:25.10","Ubuntu:26.04:LTS"]
- Database Specific Severity
- null
- Cvss Version
- 4.0
Threat ID: 6a58b4ac68715ace43da9353
Added to database: 07/16/2026, 10:38:36 UTC
Last enriched: 07/16/2026, 12:46:13 UTC
Last updated: 07/16/2026, 12:46:13 UTC
Views: 2
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