Vulnerability Report

CVE-2026-45304

RCE

Title: YAML Parser Recursive Alias Memory Exhaustion

RCE

Proof Of Concept

No public PoC currently indexed for CVE-2026-45304.

CWE Category CWE-776
Published Date Jul 14, 2026
Modified Date Jul 15, 2026
Exploit Status Not Found
Score 8.7 CVSS v4.0
Exploit Probability (EPSS)
0.80%

Vulnerability Summary

CVE-2026-45304: Symfony is a PHP framework for web and console applications and a set of reusable PHP components. Prior to 5.4.52, 6.4.40, 7.4.12, and 8.0.12, Symfony\Component\Yaml\Parser resolved YAML collection aliases recursively, allowing a small untrusted YAML input to expand into a multi-gigabyte structure and exhaust memory. This issue is fixed in versions 5.4.52, 6.4.40, 7.4.12, and 8.0.12.

Impacted Vendors

S
sensiolabs 1
A
auth0 1

Reference Links

https://github.com/symfony/symfony/commit/e77391b2e4f18821198f010d573674c8ed4a970a https://github.com/symfony/symfony/releases/tag/v5.4.52 https://github.com/symfony/symfony/releases/tag/v6.4.40 https://github.com/symfony/symfony/releases/tag/v7.4.12 https://github.com/symfony/symfony/releases/tag/v8.0.12 https://github.com/symfony/symfony/security/advisories/GHSA-4qpc-3hr4-r2p4
CVSS v4.0
Source Entity [email protected]
Severity HIGH
8.7
Attack Vector
NETWORK
Complexity
LOW
Privileges
N/A
Interaction
NONE
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
N/A
RAW VECTOR CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS v3.1
Source Entity [email protected]
Severity HIGH
7.5
Attack Vector
NETWORK
Complexity
LOW
Privileges
N/A
Interaction
NONE
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
UNCHANGED
RAW VECTOR CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2026-45304 Exploits & PoCs (Proof Of Concept)

No public PoCs found in our database for this CVE.

MODIFIED

Vulnerability data updated via NVD.

MODIFIED

Vulnerability data updated via NVD.

MODIFIED

Vulnerability data updated via NVD.

Attack Vector Matrix

Access Vector NETWORK
Complexity LOW
Privileges N/A
Interaction NONE
CVSS Vector String CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected Stack

No specific products linked.