CISO Tribune

Glossary

What is an interim CISO? The temporary security chief, defined

An interim CISO covers the security chief's duties between a departure and a permanent appointment. How filings disclose it, and why the seat still counts as open.

Term: Interim CISO · Also: Acting CISO, Interim chief information security officer
By Hadass Liza Bitton · Published October 19, 2026 · Last reviewed October 19, 2026 · 2 min read

An interim CISO is a person who carries the chief information security officer's responsibilities temporarily, between one holder's departure and a permanent appointment, or while the holder moves to another role. The interim can be an internal leader or an outside executive. On CISO Tribune's record the seat is covered, not filled, until a permanent CISO is confirmed.

How companies disclose it

Interim arrangements surface in Item 1C of Form 10-K, where a company describes which management positions are responsible for cybersecurity risk and what expertise they bring. F5's annual report for fiscal 2024, filed on 18 November 2024, says its CISO began moving to a new role inside the company in September 2024 and that it appointed an interim CISO while it searched for a permanent replacement.

GitLab's report for the fiscal year ended 31 January 2026, filed on 17 March 2026, dates its change precisely: its CISO left the role on 26 February 2026, and its vice president of security operations is acting as interim CISO during the search. Both filings describe the interim's experience, more than 25 years in each case, which is the kind of expertise detail Item 106 asks companies to give.

Why it matters to a board

A CISO change does not by itself require a current report. Form 8-K Item 5.02(b) covers the departure of the principal executive, financial, accounting and operating officers, people performing similar functions, and named executive officers. A CISO who is none of those can leave, and an interim can step in, without an 8-K. F5 described its September 2024 change in the 10-K it filed on 18 November 2024.

An interim period also tests the program. Directors should know who holds incident decision rights while the seat is covered, and how long the search is expected to take.

How CISO Tribune records it

The Wire records the top security seat only, and its gate treats interim and acting CISO titles as distinct from that seat. A seat covered by an interim therefore stays on the open seats board until a permanent appointment is confirmed. The days between the confirmed departure and that appointment count toward time to fill the CISO seat, not toward anyone's time in seat.

What it is not

An interim CISO is not a deputy CISO, a standing second-in-command, although a deputy may be the one asked to cover. It is not a virtual CISO, an ongoing outsourced arrangement with no search attached.

Related terms

Frequently asked questions

Does a company have to announce an interim CISO?
Not through a Form 8-K unless the CISO is also one of the officers Item 5.02 covers, such as the principal operating officer or a named executive officer. Some companies describe the change in Item 1C of their next Form 10-K instead, as F5 and GitLab did.
Does CISO Tribune count an interim CISO as filling the seat?
No. The Wire treats interim and acting CISO titles as distinct from the top security seat, so a seat covered by an interim stays on the open-seats board until a permanent appointment is confirmed.

Sources

Hadass Liza Bitton

Writer

Hadass Liza Bitton is a writer at CISO Tribune covering security leadership: the people who take the top security seat, the ones who leave it, and what each move signals. Reach her at hadass@cisotribune.com.

Cite this definition as “CISO Tribune glossary” with a link to this page. Corrections: /corrections. All terms: /glossary.

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