CVE-2025-14178

Heap buffer overflow in array_merge()

HIGH
8.2
CVSS Score
Published: December 27, 2025 at 07:27 PM UTC
Updated: October 13, 2026 at 09:10 AM UTC
1 product affected across 1 vendorPHP

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Severity
HIGH8.2
Exploit prediction
EPSS 0.5%
SSVC
PoC

Description

In PHP versions:8.1.* before 8.1.34, 8.2.* before 8.2.30, 8.3.* before 8.3.29, 8.4.* before 8.4.16, 8.5.* before 8.5.1, a heap buffer overflow occurs in array_merge() when the total element count of packed arrays exceeds 32-bit limits or HT_MAX_SIZE, due to an integer overflow in the precomputation of element counts using zend_hash_num_elements(). This may lead to memory corruption or crashes and affect the integrity and availability of the target server.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

PHP· PHPdrupal
95%
8.1.0 ≤ v < 8.1.348.2.0 ≤ v < 8.2.308.3.0 ≤ v < 8.3.298.4.0 ≤ v < 8.4.168.5.0 ≤ v < 8.5.18.1.*8.2.*8.3.*8.4.*8.5.*
Affected range stops below 8.1.34, so it looks safe — our inference, not a vendor statement
Affected range stops below 8.2.30, so it looks safe — our inference, not a vendor statement
Affected range stops below 8.3.29, so it looks safe — our inference, not a vendor statement
Affected range stops below 8.4.16, so it looks safe — our inference, not a vendor statement
Affected range stops below 8.5.1, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
LOW
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-787CWE-190

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