Small Sieve
Essential information
- Confidence
- 100/100
- Is family
- Yes
- Published
- 16/08/2022 21:16
- Modified
- 27/03/2026 01:07
- Revoked
- No
- Author / Source
- The MITRE Corporation
- Related entities
- 13 attack patterns (mitre), 1 intrusion sets (apt)
Aliases
GRAMDOOR
Description
[Small Sieve](https://attack.mitre.org/software/S1035) is a Telegram Bot API-based Python backdoor that has been distributed using a Nullsoft Scriptable Install System (NSIS) Installer; it has been used by [MuddyWater](https://attack.mitre.org/groups/G0069) since at least January 2022.(Citation: DHS CISA AA22-055A MuddyWater February 2022)(Citation: NCSC GCHQ Small Sieve Jan 2022)
Security researchers have also noted [Small Sieve](https://attack.mitre.org/software/S1035)'s use by UNC3313, which may be associated with [MuddyWater](https://attack.mitre.org/groups/G0069).(Citation: Mandiant UNC3313 Feb 2022)
Marking (TLP)
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