CVE-2026-91765VulnerabilityPublished 10 Nov 2026

Red Hat Security Advisory: php:8.4 security update

Affects Red Hat php:8.4Source GCVE Database

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Mentioned vulnerabilities

Authoritative record:CVE-2026-91765· High 7.5

Not known to be exploited · CVSS 7.5 High · fixed in Red Hat package updates : patch Red Hat php:8.4 soon.

Data as of 11 Nov 2026, 02:21 UTC

CVSS 3.1 base score

7.5High

How severe the flaw is on the 0–10 CVSS scale.

Patch: Available – fixed in 8.5.11, 8.4.26, 8.3.35 +1

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: None
Availability: High

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 25 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 10 Nov 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade PHP to 8.5.11, 8.4.26, 8.3.35 or 8.2.34.

Affected software

Product	Affected	Fixed in
PHP GroupPHP	Affected ≥ 8.5.*, < 8.5.11	Fixed in 8.5.11
PHP GroupPHP	Affected ≥ 8.4.*, < 8.4.26	Fixed in 8.4.26
PHP GroupPHP	Affected ≥ 8.3.*, < 8.3.35	Fixed in 8.3.35
PHP GroupPHP	Affected ≥ 8.2.*, < 8.2.34	Fixed in 8.2.34

AI-suggested

Red Hat has issued an official security update for the PHP 8.4 module in Red Hat Enterprise Linux 9 that addresses these vulnerabilities. Users should apply the update as detailed in the Red Hat advisory (https://access.redhat.com/articles/11258) to remediate the issues. No additional mitigation steps are indicated beyond applying the official update.

Description

This Red Hat security advisory addresses multiple vulnerabilities in the PHP 8.4 module for Red Hat Enterprise Linux 9. The issues include a denial of service via unbounded recursion in the SOAP parser (CVE-2026-91765), an out-of-memory bailout during request parsing that can lead to memory corruption and remote code execution (CVE-2026-109618), and a use-after-free vulnerability caused by stale request state retention during fatal error handling (CVE-2026-109619). These vulnerabilities have been rated with an important security impact by Red Hat. Updates are available to remediate these issues.

Impact

Successful exploitation of CVE-2026-91765 can cause denial of service by crashing the PHP process. CVE-2026-109618 may allow attackers to execute arbitrary code remotely due to memory corruption triggered by out-of-memory conditions during request parsing. CVE-2026-109619 can lead to use-after-free conditions, which may also be exploitable for remote code execution. These vulnerabilities affect the security and stability of PHP applications running on affected Red Hat Enterprise Linux 9 systems.

CWE-674Uncontrolled Recursion (opens in a new tab)
Class weakness
The product does not properly control the amount of recursion that takes place, consuming excessive resources, such as allocated memory or the program stack.
Implementation
Ensure that an end condition will be reached under all logic conditions. The end condition may include checking against the depth of recursion and exiting with an error if the recursion goes too deep. The complexity of the end condition contributes to the effectiveness of this action.
Implementation
Increase the stack size.
Attack patterns
Serialized Data with Nested Payloads (opens in a new tab)
Oversized Serialized Data Payloads (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-416Use After Free (opens in a new tab)
Variant weaknessLikelihood of exploit: HighCWE Top 25 (2025): #7
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.
Architecture and Design · Language Selection
Choose a language that provides automatic memory management.
Implementation · Attack Surface Reduction
When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.
OWASP Cheat Sheets
XML Security (opens in a new tab)
Mass Assignment (opens in a new tab)
OWASP ASVS 4.0.3
V13.3.1 (opens in a new tab)
V5.1.4 (opens in a new tab)
V5.1.3 (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 11 Nov 2026, 02:21 UTC

WeaknessesCWE-674, CWE-416

Technical details

References

Community reviews

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