open source PHP: security vulnerability (CVE-2026-12184)
Published Sources: Debian, BSI, Ubuntu
What is affected, what to do
It was discovered that PHP incorrectly handled certain TLS setup failures, resulting in a NULL pointer dereference. An attacker could possibly use this issue to cause PHP to crash, resulting in a denial of service.
Update open source PHP to version 8.5.6, open source PHP to version 8.4.21, open source PHP to version 8.3.32.
- Affected
- open source PHP
< *..8.5.6 - open source PHP
< *..8.4.21 - open source PHP
< *..8.3.32 - open source PHP
< *..8.2.32
- open source PHP
- Fixed in
- open source PHP
8.5.6 - open source PHP
8.4.21 - open source PHP
8.3.32 - open source PHP
8.2.32
- open source PHP
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Metrics
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Priority
No value is available for this vulnerability.
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CVSS v3
No value is available for this vulnerability.
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EPSS score
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- Severity
- Reserved
Priority (0–325)
The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first?
Read in glossary- 51.39 Methodology
Exploit maturity
An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack.
Read in glossary- no public PoC known
KEV status
The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.
Read in glossary- —
- Published
Detection rules
No NEOSEC detection rule is available for this vulnerability yet.
Classification under NIS2 and CRA
Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.
NIS2
NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.
Read in glossary- Handle the vulnerability in regular vulnerability handling under Art. 21(2)(e) NIS2.
CRA
The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.
Read in glossary- From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
ISO/IEC 27001
ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.
Read in glossary- Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.
Description
It was discovered that PHP incorrectly handled certain TLS setup failures, resulting in a NULL pointer dereference. An attacker could possibly use this issue to cause PHP to crash, resulting in a denial of service. This issue only affected Ubuntu 26.04 LTS. (CVE-2026-12184) It was discovered that PHP contained a buffer allocation flaw in the OpenSSL extension when using the AES-WRAP-PAD algorithm. An attacker could use this issue to cause PHP to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2026-14355)
Source: Debian Security Advisories, BSI WID Portal, BSI CSAF, Ubuntu Security Notices
Affected products
The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.
| Affected versions | Fixed in | ||
|---|---|---|---|
| Open Source | PHP |
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Vendors and products
Affected operating systems
| Linux | ubuntu | php8.1 | jammy |
| Linux | ubuntu | php8.3 | noble |
| Linux | debian | php8.4 | trixie |
| Linux | ubuntu | php8.5 | resolute |
Included in the same advisory
| Medium | CVE-2026-14355 | ext/openssl: Memory corruption in openssl_encrypt with AES-WRAP-PAD | 5.6 | — |
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<a href="https://intel.neosec.eu/en/cve/CVE-2026-12184"><img src="https://intel.neosec.eu/badge/cve/CVE-2026-12184.svg?lang=en" alt="CVE-2026-12184 – NEOSEC Intel" height="20"></a>