F5 BIG-IP prior 17.1.3.1/17.5.1.4/21.0.0.1 buffer overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.3$0-$5k0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in F5 BIG-IP. Impacted is an unknown function. The manipulation results in buffer overflow. This vulnerability was named CVE-2026-40067. The attack may be performed from remote. There is no available exploit. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in F5 BIG-IP. It has been classified as critical. Affected is an unknown functionality. The manipulation with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. This is going to have an impact on availability. CVE summarizes:

When a BIG-IP APM access policy is configured on a virtual server, undisclosed traffic can cause the apmd process to terminate.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

The weakness was presented by F5 as K000161056. The advisory is shared for download at my.f5.com. This vulnerability is traded as CVE-2026-40067 since 05/01/2026. 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 current price for an exploit might be approx. USD $0-$5k (estimation calculated on 05/24/2026).

The vulnerability scanner Nessus provides a plugin with the ID 316102 (F5 Networks BIG-IP : BIG-IP APM vulnerability (K000161056)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 17.1.3.1, 17.5.1.4 or 21.0.0.1 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (316102) and CERT Bund (WID-SEC-2026-1532). Once again VulDB remains the best source for vulnerability data.

Affected

  • F5 BIG-IP

Productinfo

Type

Vendor

Name

License

Website

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: Buffer overflow
CWE: CWE-120 / CWE-119
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: 316102
Nessus Name: F5 Networks BIG-IP : BIG-IP APM vulnerability (K000161056)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: BIG-IP 17.1.3.1/17.5.1.4/21.0.0.1

Timelineinfo

05/01/2026 CVE reserved
05/13/2026 +12 days Advisory disclosed
05/13/2026 +0 days VulDB entry created
05/24/2026 +11 days VulDB entry last update

Sourcesinfo

Vendor: f5.com

Advisory: K000161056
Researcher: F5
Status: Confirmed

CVE: CVE-2026-40067 (🔒)
GCVE (CVE): GCVE-0-2026-40067
GCVE (VulDB): GCVE-100-363588
CERT Bund: WID-SEC-2026-1532 - F5 BIG-IP Produkte: Mehrere Schwachstellen

Entryinfo

Created: 05/13/2026 17:49
Updated: 05/24/2026 23:39
Changes: 05/13/2026 17:49 (76), 05/17/2026 13:35 (7), 05/24/2026 23:39 (2)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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