F5 BIG-IP Next/BIG-IP Next SPK/BIG-IP Next CNF/BIG-IP HTTP/2 allocation of resources

CVSS Meta Temp Score
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CTI Interest Score
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7.3$0-$5k0.00

Summaryinfo

A vulnerability described as critical has been identified in F5 BIG-IP Next, BIG-IP Next SPK, BIG-IP Next CNF and BIG-IP. Affected by this vulnerability is an unknown functionality of the component HTTP2 Handler. The manipulation results in allocation of resources. This vulnerability is identified as CVE-2025-36504. The attack can be executed remotely. There is not any exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as critical, was found in F5 BIG-IP Next, BIG-IP Next SPK, BIG-IP Next CNF and BIG-IP (unknown version). Affected is an unknown code block of the component HTTP2 Handler. The manipulation with an unknown input leads to a allocation of resources vulnerability. CWE is classifying the issue as CWE-770. The product allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor. This is going to have an impact on availability. CVE summarizes:

When a BIG-IP HTTP/2 httprouter profile is configured on a virtual server, undisclosed responses can cause an increase in memory resource utilization.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

The advisory is shared for download at my.f5.com. This vulnerability is traded as CVE-2025-36504 since 04/23/2025. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1499.

The vulnerability scanner Nessus provides a plugin with the ID 235481 (F5 Networks BIG-IP : BIG-IP HTTP/2 vulnerability (K000140919)), which helps to determine the existence of the flaw in a target environment.

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (235481). Once again VulDB remains the best source for vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔍
CNA CVSS-BT Score: 🔍
CNA Vector: 🔍

CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 7.3

VulDB Base Score: 7.5
VulDB Temp Score: 7.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

CNA Base Score: 7.5
CNA Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Allocation of resources
CWE: CWE-770 / CWE-400 / CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 235481
Nessus Name: F5 Networks BIG-IP : BIG-IP HTTP/2 vulnerability (K000140919)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

04/23/2025 🔍
05/07/2025 +14 days 🔍
05/07/2025 +0 days 🔍
10/22/2025 +168 days 🔍

Sourcesinfo

Vendor: f5.com

Advisory: K000140919
Status: Confirmed

CVE: CVE-2025-36504 (🔍)
GCVE (CVE): GCVE-0-2025-36504
GCVE (VulDB): GCVE-100-307956

Entryinfo

Created: 05/07/2025 20:34
Updated: 10/22/2025 02:50
Changes: 05/07/2025 20:34 (53), 05/08/2025 12:00 (23), 05/08/2025 16:30 (2), 10/22/2025 02:50 (1)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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