CVE-2026-41957Network attack vector

Authenticated code execution via undisclosed deserialization

Published May 13, 2026 · Updated May 13, 2026

Deserialization in the F5 BIG-IP and BIG-IQ Configuration utility allows remote authenticated users to execute arbitrary code. F5 identifies deserialization of untrusted data but has not disclosed the affected function, input field, serialized format, or unsafe operation. A low-privileged account and network access to the Configuration utility are required; successful exploitation grants code execution on the appliance.

CVSS severity8.8
High
EPSS probability0.51%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Deserialization in the F5 BIG-IP and BIG-IQ Configuration utility allows remote authenticated users to execute arbitrary code. F5 identifies deserialization of untrusted data but has not disclosed the affected function, input field, serialized format, or unsafe operation. A low-privileged account and network access to the Configuration utility are required; successful exploitation grants code execution on the appliance.

The record

CVE
CVE-2026-41957
Published
May 13, 2026
Updated
May 13, 2026
Vendor
F5 Networks
Product
BIG-IP
Classifications
CWE-502
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. May 13, 2026CVE publishedPublication date reported by the CVE source.
  2. May 13, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=16.1.0 <*
  2. Affected versionversion=17.1.0 <17.1.3.1
  3. Affected versionversion=17.5.0 <17.5.1.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

F5 Networks · BIG-IPversion=16.1.0 <*; version=17.1.0 <17.1.3.1; version=17.5.0 <17.5.1.4
F5 Networks · BIG-IQversion=8.4.0 <8.4.1

Published CVSS scores

8.7F5CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
8.8F5CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-502Deserialization of Untrusted Data

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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