UBUNTU-CVE-2026-45077
Symfony PHP framework versions prior to 5.4.52, 6.4.40, 7.4.12, and 8.0.12 contain a vulnerability in the server:log listener that binds to 0.0.0.0:9911 by default and unserializes incoming base64-decoded messages without authentication or integrity checks. This allows any reachable host to submit crafted serialized PHP payloads that can crash the listener and potentially trigger object injection gadget effects. The issue is fixed in the specified later versions.
AI Analysis
Technical Summary
The vulnerability in Symfony's server:log listener (Symfony\Bridge\Monolog\Command\ServerLogCommand) arises because it listens on all interfaces (0.0.0.0:9911) and processes incoming messages by unserializing base64-decoded data without any authentication, integrity verification, or allowed_classes restrictions. This allows remote attackers who can reach the listener to send attacker-controlled serialized PHP payloads, which may cause a denial of service by crashing the listener and could potentially lead to object injection attacks. The vulnerability affects multiple Symfony versions prior to 5.4.52, 6.4.40, 7.4.12, and 8.0.12, where the issue has been fixed.
Potential Impact
An unauthenticated remote attacker can send malicious serialized PHP payloads to the server:log listener, causing it to crash (denial of service) and potentially enabling object injection attacks. This compromises the availability and may impact the integrity of the affected system components running vulnerable Symfony versions.
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. No vendor advisory indicates alternative mitigations or that no action is required.
UBUNTU-CVE-2026-45077
Description
Symfony PHP framework versions prior to 5.4.52, 6.4.40, 7.4.12, and 8.0.12 contain a vulnerability in the server:log listener that binds to 0.0.0.0:9911 by default and unserializes incoming base64-decoded messages without authentication or integrity checks. This allows any reachable host to submit crafted serialized PHP payloads that can crash the listener and potentially trigger object injection gadget effects. The issue is fixed in the specified later 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 vulnerability in Symfony's server:log listener (Symfony\Bridge\Monolog\Command\ServerLogCommand) arises because it listens on all interfaces (0.0.0.0:9911) and processes incoming messages by unserializing base64-decoded data without any authentication, integrity verification, or allowed_classes restrictions. This allows remote attackers who can reach the listener to send attacker-controlled serialized PHP payloads, which may cause a denial of service by crashing the listener and could potentially lead to object injection attacks. The vulnerability affects multiple Symfony versions prior to 5.4.52, 6.4.40, 7.4.12, and 8.0.12, where the issue has been fixed.
Potential Impact
An unauthenticated remote attacker can send malicious serialized PHP payloads to the server:log listener, causing it to crash (denial of service) and potentially enabling object injection attacks. This compromises the availability and may impact the integrity of the affected system components running vulnerable Symfony versions.
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. No vendor advisory indicates alternative mitigations or that no action is required.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- UBUNTU-CVE-2026-45077
- 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: 6a58b4ac68715ace43da9362
Added to database: 07/16/2026, 10:38:36 UTC
Last enriched: 07/16/2026, 12:46:57 UTC
Last updated: 07/16/2026, 12:46:57 UTC
Views: 2
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