F5 BIG-IP prior 17.1.3.1/17.5.1.4/21.0.0.1 xpath injection

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.3$0-$5k0.00

Summaryinfo

A vulnerability identified as problematic has been detected in F5 BIG-IP. The affected element is an unknown function. This manipulation causes xpath injection. The identification of this vulnerability is CVE-2026-40699. It is possible to initiate the attack remotely. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in F5 BIG-IP. It has been declared as problematic. Affected by this vulnerability is some unknown functionality. The manipulation with an unknown input leads to a xpath injection vulnerability. The CWE definition for the vulnerability is CWE-643. The product uses external input to dynamically construct an XPath expression used to retrieve data from an XML database, but it does not neutralize or incorrectly neutralizes that input. This allows an attacker to control the structure of the query. As an impact it is known to affect confidentiality. The summary by CVE is:

A vulnerability exists in the undisclosed pages in the Configuration utility that may allow a low-privileged authenticated attacker to access to undisclosed sensitive information.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

The advisory is shared at my.f5.com. This vulnerability is known as CVE-2026-40699 since 05/01/2026. The exploitation appears to be easy. The attack can be launched remotely. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 05/25/2026). MITRE ATT&CK project uses the attack technique T1055 for this issue.

The vulnerability scanner Nessus provides a plugin with the ID 316087 (F5 Networks BIG-IP : BIG-IP Configuration utility vulnerability (K000156734)), 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 (316087) and CERT Bund (WID-SEC-2026-1532). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.5
CNA Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Xpath injection
CWE: CWE-643 / CWE-74 / CWE-707
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: 316087
Nessus Name: F5 Networks BIG-IP : BIG-IP Configuration utility vulnerability (K000156734)

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
05/25/2026 +12 days VulDB entry last update

Sourcesinfo

Vendor: f5.com

Advisory: K000150515
Status: Confirmed

CVE: CVE-2026-40699 (🔒)
GCVE (CVE): GCVE-0-2026-40699
GCVE (VulDB): GCVE-100-363589
CERT Bund: WID-SEC-2026-1532 - F5 BIG-IP Produkte: Mehrere Schwachstellen

Entryinfo

Created: 05/13/2026 17:49
Updated: 05/25/2026 03:49
Changes: 05/13/2026 17:49 (74), 05/17/2026 13:35 (7), 05/25/2026 03:49 (2)
Complete: 🔍
Cache ID: 216::103

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