Ambiguous zone abbreviations and bare offsets

'IST' means India, Ireland, OR Israel; 'CST' means US Central, China, OR Cuba; 'EST' is used by the US and Australia. Three-letter abbreviations and bare offsets cannot identify a zone or its DST rules.

Class

Case to account for

Affects

1 conversion

Detection

Input is an abbreviation or a numeric offset rather than an IANA zone id.

Mitigation

Require canonical IANA zone ids (Area/Location). Reject abbreviations.

Affected conversions

Timestamp + zonehour-of-week slot

OPEN