שיעבוד is a term of any subjugation of an asset of one owner to another, including mortgages, liens etc. See Ma'ot terminology: מְשׁוּעבַּד = לועזית: encumbered (http://www.maot.co.il/lex3/glossary/g_4699.asp) = רכוש שיש למישהו קניין לגביו אבל יש נגדו תביעה או התחייבות להעניקו לאחר
The most general term, I think, would be lien rather than mortgage. The Securities Regulations (Preparation of Financial Reports) require listing the liabilities of the corporation, secured through the lien on its assets, by category of the type of שיעבוד and משועבד asset. If it is an account, the term hypothecated is applicable (http://www.maot.co.il/lex3/glossary/g_2954.asp). For other assets, pledged is more appropriate (http://www.maot.co.il/lex3/glossary/g_5080.asp). Another option is under obligation (http://www.maot.co.il/lex3/glossary/g_2300.asp).

The above suggestions are the broadest. With further context it is possible to choose a more precise term. For example, Under English law and in common law jurisdictions derived from English law, there are eight types of proprietary security interests: (1) 'true' legal mortgage; (2) equitable mortgage; (3) statutory mortgage; (4) fixed equitable charge, or bill of sale; (5) floating equitable charge; (6) pledge, or pawn; (7) legal lien; (8) equitable lien; and (9) hypothecation, or trust receipt. (WikiPedia, link below)