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PatchSiren cyber security CVE debrief

CVE-2026-41953 F5 CVE debrief

CVE-2026-41953 is a high-severity vulnerability in BIG-IP systems that allows a highly privileged, authenticated attacker to modify configuration objects, resulting in privilege escalation. The vulnerability has a CVSS score of 8.5 and is considered HIGH. F5 has provided mitigation guidance for this issue. Software versions that have reached End of Technical Support (EoTS) are not evaluated. The CVE was published on May 13, 2026, and was last modified on June 24, 2026.

Vendor
F5
Product
BIG-IP
CVSS
HIGH 8.5
CISA KEV
Not listed in stored evidence
Original CVE published
2026-05-13
Original CVE updated
2026-06-24
Advisory published
2026-05-13
Advisory updated
2026-06-24

Who should care

Organizations using BIG-IP systems, particularly those with highly privileged users, should be aware of this vulnerability. The vulnerability requires a highly privileged, authenticated attacker, and the impact is privilege escalation. F5 has provided mitigation guidance for this issue.

Technical summary

The vulnerability exists in BIG-IP systems where a highly privileged, authenticated attacker with at least the Resource Administrator role can modify configuration objects resulting in privilege escalation. The CVSS vector for this vulnerability is CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. The weakness associated with this vulnerability is CWE-77.

Defensive priority

This vulnerability has a high CVSS score of 8.5 and requires immediate attention. Organizations should apply mitigation guidance provided by F5 as soon as possible.

Recommended defensive actions

  • Apply mitigation guidance provided by F5.
  • Restrict access to highly privileged users.
  • Monitor BIG-IP systems for suspicious activity.
  • Ensure that BIG-IP systems are running with the latest software version.
  • Implement compensating controls to detect and prevent privilege escalation.

Evidence notes

The CVE record and NVD detail provide information on the vulnerability, including its CVSS score and vector. F5 has provided mitigation guidance for this issue. The vulnerability requires a highly privileged, authenticated attacker, and the impact is privilege escalation.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-41953 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-41953

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-41953 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-41953

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.