Cybersecurity Threat Spotlight: HermeticWiper, SDUser, and Xenomorph

This has been a busy month for cyber attackers, and the Cisco Umbrella team – in conjunction with Cisco Talos – has observed several new threats for users to be aware of.

In this month’s edition of the Cybersecurity Threat Spotlight, we discuss a wiper making its way through Ukraine, a dropper targeting India and China, and a newly discovered Trojan targeting EU banks.

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HermeticWiper

Threat Type: Wiper

Attack Chain:

Graphic showing the attack chain for HermeticWiper. The attack chain proceeds as follows: stolen credentials, network access, direct wiper deployment, data destruction. The graphic indicates that Cisco Secure protects users from stolen credentials and data destruction.

Description: HermeticWiper is a data destructing malware observed in attacks targeting Ukraine. This wiper comes as a small executable with a valid digital signature issued to “Hermetica Digital Ltd.” The malware leverages embedded resources to interact with storage devices present on infected systems. The applicable embedded driver is extracted, loaded into the wiper’s process memory space, decompressed, and written to the disk before the wipe process. The wiper disables the generation of crash dumps and corrupts the first 512 bytes to destroy the MBR of physical drives. For partitions, it disables the Volume Shadow Copy Service and uses different destructive mechanisms on the partitions depending on whether they’re FAT type or NTFS type. The wiper also attempts to corrupt housekeeping files. During the final stage, HermeticWiper waits for all sleeping threads to complete and initiates a reboot to ensure the success of the wiping activity.

HermeticWiper Spotlight: Cisco Talos has become aware of a series of wiper attacks going on inside Ukraine. One of the wipers used in these attacks has been dubbed “HermeticWiper.” Deployment of this destructive malware began on February 23, 2022. The malware has two components designed for destruction: one targeting the Master Boot Record (MBR) and another targeting partitions.

Target Geolocations: Ukraine
Target Data: Physical Drivers, Partitions
Target Businesses: Government Sector
Exploits: N/A

Mitre ATT&CK for HermeticWiper

Initial Access:
Valid Accounts

Discovery:
System Information Discovery
File and Directory Discovery

Persistence:
Create or Modify System Process: Windows Service

Execution:
Native API

Evasion:
Modify Registry

Impact:
Disk Wipe: Disk Structure Wipe
Inhibit System Recovery
Service Stop
System Shutdown/Reboot

Privilege Escalation:
Access Token Manipulation

IOCs1

Hashes:
0385eeab00e946a302b24a91dea4187c1210597b8e17cd9e2230450f5ece21da
1bc44eef75779e3ca1eefb8ff5a64807dbc942b1e4a2672d77b9f6928d292591
2c10b2ec0b995b88c27d141d6f7b14d6b8177c52818687e4ff8e6ecf53adf5bf
3c557727953a8f6b4788984464fb77741b821991acbf5e746aebdd02615b1767

Additional Information
Threat Advisory: Hermetic Wiper

Which Cisco Secure Products Can Block
Cisco Secure Endpoint
Cisco Secure Email
Cisco Secure Firewall/Secure IPS
Cisco Secure Malware Analytics
Cisco Umbrella


SDUser

Threat Type: Dropper

Attack Chain:

A graphic showing the attack chain of SDUser, which is as follows: malspam to download weaponized document to malicious macros to SDUser payload to follow-up malware. The graphic indicates that Cisco Secure products protect users from downloading weaponized documents and follow-up malware.

Description: SDUser is a VBA-based dropper that is used by Advanced Persistent Threat (APT) groups. The functionality of the payload includes command and control protocol, anti-sandboxing techniques, and a reverse shell mechanism.

SDUser Spotlight: In June 2021, Cisco Talos researchers discovered a malicious Excel spreadsheet that attempted to drop a previously unknown RAT. A month later, they discovered another closely related spreadsheet. These samples were internally referred to as “SDUser” sampled due to the specific PDB string left in the binary payload.

More recent analysis shows similar code being used by two different APT groups: Transparent Tribe, which targets organizations in India, and Donut, which targets organizations in Pakistan and China. These two different threat actors may use code from the same source in their attacks, which means that their attacks would display similarities despite being conducted by different groups. Code reuse, adopting techniques from successful attacks, and deliberate integration of evidence designed to fool analysts can disguise the true perpetrator and lead to these attacks being attributed to different groups.

Target Geolocations: Pakistan, China
Target Data: User Credentials, Browser Data, Sensitive Information
Target Businesses: Any
Exploits: N/A

Mitre ATT&CK for SDUser

Initial Access:
Phishing: Spearphishing Attachment

Discovery:
Peripheral Device Discovery
Query Registry

Execution:
Command and Scripting Interpreter

Evasion:
Obfuscated Files or Information
Virtualization/Sandbox Evasion: System Checks

Command and Control:
Application Layer Protocol
Web Service

IOCs1

Domains:
microsoft-updates[.]servehttp[.]com
microsoft-patches[.]servehttp[.]com
microsoft-docs[.]myftp[.]org

IPs:
45.153.240[.]66
46.30.188[.]222

Additional Information:
What’s with the shared VBA code between Transparent Tribe and other threat actors?

Which Cisco Secure Products Can Block:
Cisco Secure Endpoint
Cisco Secure Email
Cisco Secure Firewall/Secure IPS
Cisco Secure Malware Analytics
Cisco Umbrella
Cisco Secure Web Appliance


Xenomorph

Threat Type: Mobile Trojan

Attack Chain:

A graphic showing the attack chain of Xenomorph, which is as follows: Trojanized app to data logging to data exfiltration. The graphic indicates that Cisco Secure products protect against data exfiltration.

Description: Xenomorph is an Android Banking Trojan. It is capable of stealing credentials via overlay attack, and it uses SMS and notification interception to log and use potential 2FA tokens. Stolen data is sent to the C2 for further exploitation.

Xenomorph Spotlight: Xenomorph was initially discovered in February 2022. It is distributed through the official Google Play Store. It targets users of 56 different European banks and cryptocurrency wallets. Capabilities include – but are not limited to – stealing credentials, SMS and notification interception, excessive logging, and data exfiltration. The core engine is designed as a modular system and still appears to be in the development stage. Malware heavily relies on the overlay attack mechanism to steal personally identifiable information (PII) and other sensitive data. Collected data is exfiltrated to an attacker-controlled server using the open-source project RetroFit2.

Target Geolocations: EU
Target Data: User Credentials, Browser Data, Sensitive Information
Target Businesses: Any
Exploits: N/A

Mitre ATT&CK for Xenomorph

Initial Access:
Deliver Malicious App via Authorized App Store

Execution:
Native Code

Evasion:
Masquerading as Legitimate Application

Credential Access:
Capture SMS Messages
Input Capture

Command and Control:
Standard Application Layer Protocol

Exfiltration:
Data Encryption
Standard Application Layer Protocol

IOCs1

Domains:
simpleyo5[.]tk   
simpleyo5[.]cf   
art12sec[.]ga    
kart12sec[.]gq   
homeandofficedeal[.]com

Additional Information:
Xenomorph: A newly hatched Banking Trojan

Which Cisco Secure Products Can Block
Cisco Secure Firewall/Secure IPS
Cisco Secure Malware Analytics
Cisco Umbrella
Cisco Secure Web Appliance

Source :
https://umbrella.cisco.com/blog/cybersecurity-threat-spotlight-hermeticwiper-sduser-xenomorph

Hackers can crash Cisco Secure Email gateways using malicious emails

Cisco has addressed a high severity vulnerability that could allow remote attackers to crash Cisco Secure Email appliances using maliciously crafted email messages.

The security flaw (tracked as CVE-2022-20653) was found in DNS-based Authentication of Named Entities (DANE), a Cisco AsyncOS Software component used by Cisco Secure Email to check emails for spam, phishing, malware, and other threats.

This bug is due to an insufficient error handling issue in DNS name resolution found and reported to Cisco by Rijksoverheid Dienst ICT Uitvoering (DICTU) security researchers.

“An attacker could exploit this vulnerability by sending specially formatted email messages that are processed by an affected device,” Cisco explained.

“A successful exploit could allow the attacker to cause the device to become unreachable from management interfaces or to process additional email messages for a period of time until the device recovers, resulting in a DoS [Denial-of-Service] condition.”

To make things even worse, continued attacks can cause the targeted devices to become completely unavailable, which results in a persistent DoS condition.

The company’s Product Security Incident Response Team (PSIRT) said that it found no evidence of malicious exploitation in the wild before the security advisory was published on Wednesday.

Vulnerable component not enabled by default

While the security vulnerability can be exploited remotely by unauthenticated attackers, Cisco says the vulnerable DANE email verification component is not enabled by default.

Admins can check if DANE is configured by going to the Mail Policies > Destination Controls > Add Destination web UI page and confirming whether the DANE Support option is toggled on.

Cisco has also confirmed that CVE-2022-20653 does not impact Web Security Appliance (WSA) and Secure Email and Web Manager or devices without the DANE feature enabled.

The company also provided a workaround requiring customers to configure bounce messages from Cisco ESA instead of from downstream dependent mail servers to block exploitation attempts.

Earlier this month, Cisco patched several maximum severity flaws with proof-of-concept exploit code available that would enable threat actors to take control of Small Business RV Series routers without authentication.

Source :
https://www.bleepingcomputer.com/news/security/hackers-can-crash-cisco-secure-email-gateways-using-malicious-emails/

Critical SonicWall firewall patch not released for all devices

Security hardware manufacturer SonicWall has fixed a critical vulnerability in the SonicOS security operating system that allows denial of service (DoS) attacks and could lead to remote code execution (RCE).

The security flaw is a stack-based buffer overflow weakness with a 9.4 CVSS severity score and impacting multiple SonicWall firewalls.

Tracked as CVE-2022-22274, the bug affects TZ Series entry-level desktop form factor next-generation firewalls (NGFW) for small- and medium-sized businesses (SMBs), Network Security Virtual (NSv series) firewalls designed to secure the cloud, and Network Security services platform (NSsp) high-end firewalls.

Exploitable remotely without authentication

Unauthenticated attackers can exploit the flaw remotely, via HTTP requests, in low complexity attacks that don’t require user interaction “to cause Denial of Service (DoS) or potentially results in code execution in the firewall.”

The SonicWall Product Security Incident Response Team (PSIRT) says there are no reports of public proof-of-concept (PoC) exploits, and it found no evidence of exploitation in attacks.

The company has released patches for all impacted SonicOS versions and firewalls and urged customers to update all affected products.

“SonicWall strongly urges organizations using impacted SonicWall firewalls listed below to follow the provided guidance,” the company said in a security advisory published on Friday.

ProductImpacted PlatformsImpacted VersionFixed Version
SonicWall FireWallsTZ270, TZ270W, TZ370, TZ370W, TZ470, TZ470W, TZ570, TZ570W, TZ570P, TZ670, NSa 2700, NSa 3700, NSa 4700, NSa 5700, NSa 6700, NSsp 10700, NSsp 11700, NSsp 13700, Nsv 270, NSv 470, NSv 8707.0.1-5050 and earlier7.0.1-5051 and higher
SonicWall NSsp FirewallNSsp 157007.0.1-R579 and earlierMid-April (Hotfix build 7.0.1-5030-HF-R844)
SonicWall NSv FirewallsNSv 10, NSv 25, NSv 50, Nsv 100, NSv 200, Nsv, 300, NSv 400, NSv 800, NSv 16006.5.4.4-44v-21-1452 and earlier6.5.4.4-44v-21-1519 and higher

NSsp 15700 firewall gets hotfix, full patch in April

The only affected firewall still waiting for a patch against CVE-2022-22274 is the NSsp 15700 enterprise-class high-speed firewall.

While a hotfix is already available for those reaching out to the support team, SonicWall estimates that a full patch to block potential attacks targeting this firewall will be released in roughly two weeks.

“For NSsp 15700, continue with the temporary mitigation to avoid exploitation or reach out to the SonicWall support team who can provide you with a hotfix firmware (7.0.1-5030-HF-R844),” the company explained.

“SonicWall expects an official firmware version with necessary patches for NSsp15700 to be available in mid-April 2022.”

Temporary workaround available

SonicWall also provides a temporary workaround to remove the exploitation vector on systems that cannot be immediately patched.

As the security vendor explained, admins are required to only allow access to the SonicOS management interface to trusted sources.

“Until the [..] patches can be applied, SonicWall PSIRT strongly recommends that administrators limit SonicOS management access to trusted sources (and/or disable management access from untrusted internet sources) by modifying the existing SonicOS Management access rules (SSH/HTTPS/HTTP Management),” SonicWall added.

The updated access rules will ensure that the impacted devices “only allow management access from trusted source IP addresses.”

The company’s support website also provides customers with more information on how to restrict admin access and tips on when to allow access to the firewalls’ web management interface.

“SonicWall has proactively communicated mitigation guidance to any impacted organizations,” the security vendor told BleepingComputer. 

Source :
https://www.bleepingcomputer.com/news/security/critical-sonicwall-firewall-patch-not-released-for-all-devices/