Administrative privilege escalation via stack buffer overflow
Published May 13, 2026 · Updated May 13, 2026
A stack-based buffer overflow in F5 BIG-IP allows remote authenticated users with administrative access to escalate privileges. F5 identifies the locus only as BIG-IP LTM monitors and does not disclose the affected function, input, or overwrite operation. Exploitation requires administrative access and Appliance mode; success crosses that mode’s security boundary, while further post-boundary actions remain undisclosed.
Summary
What happened
A stack-based buffer overflow in F5 BIG-IP allows remote authenticated users with administrative access to escalate privileges. F5 identifies the locus only as BIG-IP LTM monitors and does not disclose the affected function, input, or overwrite operation. Exploitation requires administrative access and Appliance mode; success crosses that mode’s security boundary, while further post-boundary actions remain undisclosed.
The record
- CVE
- CVE-2026-42919
- Published
- May 13, 2026
- Updated
- May 13, 2026
- Vendor
- F5 Networks
- Product
- BIG-IP
- Classifications
- CWE-121, T1068
- Attack vector
- network
- Privileges
- admin
Timeline
How it unfolded
- May 13, 2026CVE publishedPublication date reported by the CVE source.
- 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.
- Affected versionversion=16.1.0 <*
- Affected versionversion=17.1.0 <17.1.3.1
- Affected versionversion=17.5.0 <17.5.1.4
- Affected versionversion=21.0.0 <21.0.0.1
What conditions does exploitation require?
What is affected?
Published CVSS scores
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.
Weakness, pattern, technique
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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