2026-07-24HIGHexploited16-nation advisory: Russia's LAUNDRY BEAR exfiltrates government mail through a view-based Zimbra exploit, and patching alone does not evict it
Ulej / Flowerbed
tool · tool:ulej-flowerbed
LAUNDRY BEAR's custom zero-click exfiltration capability for CVE-2025-66376 in Zimbra Collaboration Suite (CISA joint advisory AA26-204A, 2026-07-23): 'Ulej' (Russian for beehive) is the client-side JavaScript payload that harvests webmail data via 12 asynchronous Zimbra SOAP calls and mints a persistent IMAP application passcode; 'Flowerbed' is the Dockerised (Catcher/Certbot/Nginx/Gardener) DNS-and-HTTPS collection backend, assessed by CISA as showing indications of AI-assisted development. Proofpoint tracks the associated post-exploitation credential-theft/persistence tooling as ZimReaper.
Aliases: Улей, beehive, ZimReaper
Coverage
2
1 about it · 1 mention · first 2026-05-18 → last 2026-10-21
Latest activity
2026-07-25
16-nation advisory: Russia's LAUNDRY BEAR exfiltrates government mail through a view-based Zimbra exploit…
Peak priority
high
1 high
Targets
public-sector
sectors: public-sector, energy, defense · regions: europe
Sources cited
14
10 hosts
2026-05-182 appearances2026-07-24
Action items (3)
Do-now tasks recorded on the entries about Ulej / Flowerbed, newest first. Check the date before acting on an older one.
- Confirm every on-prem Zimbra Collaboration Suite instance is on ZCS ≥ 10.0.18 or ≥ 10.1.13 specifically for CVE-2025-66376; this is a distinct patch from the ZCS 10.1.19 and 10.1.20 fixes tracked earlier this month.2026-07-24CVE-2025-66376
- On any ZCS account suspected of exposure, revoke all application-specific passwords and regenerate 2FA scratch codes, then disable IMAP where it is not required, patching stops the next crafted email but does not revoke access an earlier one already established.2026-07-24CVE-2025-66376
- On any Zimbra account touched by the CVE-2025-66376 campaign, revoke application-specific passwords via the admin console, not just reset the user password: the attacker-created 'ZimbraWeb' app-password survives a password reset and the patch and grants standalone IMAP/POP3/SMTP mailbox access.2026-07-24CVE-2025-66376
Defender insights
What each entry about Ulej / Flowerbed tells a defender to do, newest first.
Latest update · triage
Relationships explore in graph
Typed, source-stated connections from the entity registry; each edge cites the entry whose reporting establishes it.
used by
Story timeline
Every entry that names Ulej / Flowerbed, newest first. Rows tagged mention only name it in passing: they are listed for completeness and add nothing to the action items, pivots or ATT&CK profile on this page.
- 2026-07-24Russian state actor LAUNDRY BEAR weaponised a Zimbra webmail zero-click (CVE-2025-66376) for mailbox exfiltration, now exposed in a 16-nation joint advisory
- 2026-05-18CVE-2026-42897: Exchange OWA cross-site scripting exploited by TA488 with the OWAReaper implant; fixed since the June 2026 Security Update, which does not remove the mitigation
Hunting pivots
CVEs (exploited first)
ATT&CK techniques (12 across 12 tactics)
12 techniques observed across 1 entry about this entity, derived from entry metadata and body evidence, never asserted without a published entry behind it · pinned to MITRE ATT&CK v20.0 · compare on the matrix · Navigator layer (JSON)
- Resource DevelopmentStage Capabilities
- Initial AccessPhishing
- ExecutionCommand and Scripting Interpreter: JavaScript · Exploitation for Client Execution
- PersistenceAccount Manipulation · Modify Authentication Process: Multi-Factor Authentication
- Privilege EscalationAccount Manipulation
- StealthObfuscated Files or Information: SVG Smuggling
- Defense ImpairmentModify Authentication Process: Multi-Factor Authentication
- Credential AccessSteal Web Session Cookie · Modify Authentication Process: Multi-Factor Authentication
- DiscoveryAccount Discovery: Email Account
- CollectionEmail Collection: Remote Email Collection
- Command and ControlApplication Layer Protocol: DNS
- ExfiltrationExfiltration Over Alternative Protocol: Exfiltration Over Unencrypted Non-C2 Protocol
Resource Development TA0042
T1608Stage Capabilities×1
Adversaries may upload, install, or otherwise set up capabilities that can be used during targeting. To support their operations, an adversary may need to take capabilities they developed (Develop Capabilities) or obtained (Obtain Capabilities) and stage them on infrastructure under their control. These capabilities may be staged on infrastructure that was previously purchased/rented by the adversary (Acquire Infrastructure) or was otherwise compromised by them (Compromise Infrastructure). Capabilities may also be staged on web services, such as GitHub or Pastebin, or on Platform-as-a-Service (PaaS) offerings that enable users to easily provision applications.
Evidence: 2026-07-24/laundry-bear-zimbra-zero-click-cve-2025-66376 · ATT&CK page ↗
Initial Access TA0001
T1566Phishing×1
Adversaries may send phishing messages to gain access to victim systems. All forms of phishing are electronically delivered social engineering. Phishing can be targeted, known as spearphishing. In spearphishing, a specific individual, company, or industry will be targeted by the adversary. More generally, adversaries can conduct non-targeted phishing, such as in mass malware spam campaigns.
Evidence: 2026-07-24/laundry-bear-zimbra-zero-click-cve-2025-66376 · ATT&CK page ↗
Execution TA0002
T1059.007Command and Scripting Interpreter: JavaScript×1
Adversaries may abuse various implementations of JavaScript for execution. JavaScript (JS) is a platform-independent scripting language (compiled just-in-time at runtime) commonly associated with scripts in webpages, though JS can be executed in runtime environments outside the browser.
Evidence: 2026-07-24/laundry-bear-zimbra-zero-click-cve-2025-66376 · ATT&CK page ↗
T1203Exploitation for Client Execution×1
Adversaries may exploit software vulnerabilities in client applications to execute code. Vulnerabilities can exist in software due to unsecure coding practices that can lead to unanticipated behavior. Adversaries can take advantage of certain vulnerabilities through targeted exploitation for the purpose of arbitrary code execution. Oftentimes the most valuable exploits to an offensive toolkit are those that can be used to obtain code execution on a remote system because they can be used to gain access to that system. Users will expect to see files related to the applications they commonly used to do work, so they are a useful target for exploit research and development because of their high utility.
Evidence: 2026-07-24/laundry-bear-zimbra-zero-click-cve-2025-66376 · ATT&CK page ↗
Persistence TA0003
T1098Account Manipulation×1
Adversaries may manipulate accounts to maintain and/or elevate access to victim systems. Account manipulation may consist of any action that preserves or modifies adversary access to a compromised account, such as modifying credentials or permission groups. These actions could also include account activity designed to subvert security policies, such as performing iterative password updates to bypass password duration policies and preserve the life of compromised credentials.
Evidence: 2026-07-24/laundry-bear-zimbra-zero-click-cve-2025-66376 · ATT&CK page ↗
T1556.006Modify Authentication Process: Multi-Factor Authentication×1
Adversaries may disable or modify multi-factor authentication (MFA) mechanisms to enable persistent access to compromised accounts.
Evidence: 2026-07-24/laundry-bear-zimbra-zero-click-cve-2025-66376 · ATT&CK page ↗
Privilege Escalation TA0004
T1098Account Manipulation×1
Adversaries may manipulate accounts to maintain and/or elevate access to victim systems. Account manipulation may consist of any action that preserves or modifies adversary access to a compromised account, such as modifying credentials or permission groups. These actions could also include account activity designed to subvert security policies, such as performing iterative password updates to bypass password duration policies and preserve the life of compromised credentials.
Evidence: 2026-07-24/laundry-bear-zimbra-zero-click-cve-2025-66376 · ATT&CK page ↗
Stealth TA0005
T1027.017Obfuscated Files or Information: SVG Smuggling×1
Adversaries may smuggle data and files past content filters by hiding malicious payloads inside of seemingly benign SVG files. SVGs, or Scalable Vector Graphics, are vector-based image files constructed using XML. As such, they can legitimately include `<script>` tags that enable adversaries to include malicious JavaScript payloads. However, SVGs may appear less suspicious to users than other types of executable files, as they are often treated as image files.
Evidence: 2026-07-24/laundry-bear-zimbra-zero-click-cve-2025-66376 · ATT&CK page ↗
Defense Impairment TA0112
T1556.006Modify Authentication Process: Multi-Factor Authentication×1
Adversaries may disable or modify multi-factor authentication (MFA) mechanisms to enable persistent access to compromised accounts.
Evidence: 2026-07-24/laundry-bear-zimbra-zero-click-cve-2025-66376 · ATT&CK page ↗
Credential Access TA0006
T1539Steal Web Session Cookie×1
An adversary may steal web application or service session cookies and use them to gain access to web applications or Internet services as an authenticated user without needing credentials. Web applications and services often use session cookies as an authentication token after a user has authenticated to a website.
Evidence: 2026-07-24/laundry-bear-zimbra-zero-click-cve-2025-66376 · ATT&CK page ↗
T1556.006Modify Authentication Process: Multi-Factor Authentication×1
Adversaries may disable or modify multi-factor authentication (MFA) mechanisms to enable persistent access to compromised accounts.
Evidence: 2026-07-24/laundry-bear-zimbra-zero-click-cve-2025-66376 · ATT&CK page ↗
Discovery TA0007
T1087.003Account Discovery: Email Account×1
Adversaries may attempt to get a listing of email addresses and accounts. Adversaries may try to dump Exchange address lists such as global address lists (GALs).
Evidence: 2026-07-24/laundry-bear-zimbra-zero-click-cve-2025-66376 · ATT&CK page ↗
Collection TA0009
T1114.002Email Collection: Remote Email Collection×1
Adversaries may target an Exchange server, Office 365, or Google Workspace to collect sensitive information. Adversaries may leverage a user's credentials and interact directly with the Exchange server to acquire information from within a network. Adversaries may also access externally facing Exchange services, Office 365, or Google Workspace to access email using credentials or access tokens. Tools such as MailSniper can be used to automate searches for specific keywords.
Evidence: 2026-07-24/laundry-bear-zimbra-zero-click-cve-2025-66376 · ATT&CK page ↗
Command and Control TA0011
T1071.004Application Layer Protocol: DNS×1
Adversaries may communicate using the Domain Name System (DNS) application layer protocol to avoid detection/network filtering by blending in with existing traffic. Commands to the remote system, and often the results of those commands, will be embedded within the protocol traffic between the client and server.
Evidence: 2026-07-24/laundry-bear-zimbra-zero-click-cve-2025-66376 · ATT&CK page ↗
Exfiltration TA0010
T1048.003Exfiltration Over Alternative Protocol: Exfiltration Over Unencrypted Non-C2 Protocol×1
Adversaries may steal data by exfiltrating it over an un-encrypted network protocol other than that of the existing command and control channel. The data may also be sent to an alternate network location from the main command and control server.
Evidence: 2026-07-24/laundry-bear-zimbra-zero-click-cve-2025-66376 · ATT&CK page ↗
Entries about Ulej / Flowerbed (1)
Co-occurring entities
Derived: referenced by the same focused operational entries (weekly summaries and report roundups don't count); ×N counts the shared entries.
- LAUNDRY BEAR×2
- Microsoft Exchange Server×1
- Microsoft Exchange Server Outlook Web Access stored XSS (CWE-79, CVSS 3.1 8.1) exploited by TA488/LAUNDRY BEAR with the OWAReaper implant; CISA KEV 2026-05-15; fixed in the June 2026 Exchange SU, July 2026 SU recommended; mitigations must be removed by hand×1
- OWAReaper×1
- TA458×1
- Zimbra Collaboration×1
- Zimbra Collaboration Suite Classic Web Client stored XSS (view-based/zero-click) exploited by Russian actor LAUNDRY BEAR; CVSS 7.2 (MITRE)/6.1 (NVD); CISA KEV; patched ZCS 10.0.18/10.1.13×1
Where this entity is cited
Source distribution
- techcommunity.microsoft.com3 (21%)
- cisa.gov2 (14%)
- proofpoint.com2 (14%)
- learn.microsoft.com1 (7%)
- msrc.microsoft.com1 (7%)
- ncsc.gov.uk1 (7%)
- security-hub.ncsc.admin.ch1 (7%)
- thehackernews.com1 (7%)
- other2 (14%)
All cited sources (14)
- cisa.govCISA / NSA / FBI + allied agencies from 16 nations (joint CSA AA26-204A)https://www.cisa.gov/news-events/cybersecurity-advisories/aa26-204a
- cisa.govCISA KEV cataloghttps://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json
- learn.microsoft.comMicrosoft Learnhttps://learn.microsoft.com/en-us/exchange/plan-and-deploy/post-installation-tasks/security-best-practices/exchange-emergency-mitigation-service
- msrc.microsoft.comMicrosoft Security Response Centerhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42897
- ncsc.gov.ukNCSC-UKhttps://www.ncsc.gov.uk/news/uk-and-partners-expose-russian-state-supported-actors-for-new-zero-click-phishing-campaign
- proofpoint.comProofpointhttps://www.proofpoint.com/us/blog/threat-insight/cleaning-out-inboxes-ta488-comes-outlook-another-half-click-exploit
- proofpoint.comProofpointhttps://www.proofpoint.com/us/blog/threat-insight/ta488-targets-zimbra-mailservers-half-click-exploits
- security-hub.ncsc.admin.chNCSC Switzerland (Cyber Security Hub)https://security-hub.ncsc.admin.ch/#/posts/12577
- techcommunity.microsoft.comMicrosoft Exchange Team Bloghttps://techcommunity.microsoft.com/blog/exchange/addressing-exchange-server-may-2026-vulnerability-cve-2026-42897/4518498
- techcommunity.microsoft.comMicrosoft Exchange Team Bloghttps://techcommunity.microsoft.com/blog/exchange/released-july-2026-exchange-server-security-updates/4534146
- techcommunity.microsoft.comMicrosoft Exchange Team Bloghttps://techcommunity.microsoft.com/blog/exchange/released-june-2026-exchange-server-security-updates/4524491
- thehackernews.comThe Hacker News, 2026-07-23https://thehackernews.com/2026/07/russian-espionage-group-exploited.html
- therecord.mediaThe Record (Recorded Future News)https://therecord.media/zimbra-webmail-zero-click-phishing-russia-laundry-bear
- unit42.paloaltonetworks.comPalo Alto Networks Unit 42https://unit42.paloaltonetworks.com/russian-webmail-espionage/