Full Report
This report provides statistics on the number of new ransomware samples collected, the number of affected systems, and affected companies in April 2025, as well as key ransomware issues in and out of Korea. Below is a summary of the report. Disclaimer: The number of ransomware samples and damaged systems is based on the […]
Analysis Summary
This report is based on statistics and observations aggregated over time, rather than detailing a single, specific security incident with a defined timeline of attack and response. Therefore, the structured timeline format below will reflect the *general scope and nature* of the reported ransomware activity observed in April 2025, as opposed to a specific case.
# Incident Report: April 2025 Ransomware Landscape Summary
## Executive Summary
This summary details the observed ransomware activity in April 2025, characterized by a relative increase in newly collected ransomware samples compared to the previous month (March). The primary impact reported is through data published on Dedicated Leak Sites (DLS) by various ransomware groups, indicating successful exfiltration attempts across multiple organizations. Specific response actions related to individual breaches are not provided, only aggregate collection and statistical analysis.
## Incident Details
- **Discovery Date:** Ongoing collection, statistics reported for April 2025.
- **Incident Date:** Activity spanned throughout April 2025.
- **Affected Organization:** Multiple organizations globally (details aggregated via DLS monitoring).
- **Sector:** Not specified (general industry coverage).
- **Geography:** Global, with specific mention of activity impacting Korea (in/out).
## Timeline of Events
Since this is a statistical summary, a precise single incident timeline is unavailable. The reporting covers activity during **April 2025**.
### Initial Access
- **Date/Time:** Ongoing throughout April 2025.
- **Vector:** Not explicitly detailed, but implied through ransomware deployment leading to DLS postings.
- **Details:** Reliance on detection signatures for new samples collected.
### Lateral Movement
- *Not specified in the provided summary.*
### Data Exfiltration/Impact
- **What was stolen or damaged:** Data exfiltrated, leading to public listing on Dedicated Leak Sites (DLS) by confirmed ransomware groups.
### Detection & Response
- **How it was discovered:** Detection based on AhnLab's continuously updated malware signature database and monitoring of public Dedicated Leak Sites (DLS) via ATIP infrastructure.
- **Response actions taken:** Collection and statistical reporting of samples, affected systems, and listed companies. (No specific containment/eradication details for individual breaches provided).
## Attack Methodology
The summary focuses on **Outcomes** (DLS listings) rather than a full MITRE ATT&CK breakdown of a single event.
- **Initial Access:** Implied through ransomware execution.
- **Persistence:** *Not specified*
- **Privilege Escalation:** *Not specified*
- **Defense Evasion:** *Not specified*
- **Credential Access:** *Not specified*
- **Discovery:** *Not specified*
- **Lateral Movement:** *Not specified*
- **Collection:** Data gathering necessary to result in DLS postings.
- **Exfiltration:** Successful data theft leading to public shaming/extortion.
- **Impact:** Operational disruption and data exposure confirmed by DLS presence.
## Impact Assessment
- **Financial:** Not quantified.
- **Data Breach:** Type and volume of data not specified, but confirmed successful data exfiltration leading to DLS publication.
- **Operational:** Implied system compromise requiring remediation due to ransomware execution.
- **Reputational:** High reputational damage due to public listing on DLS.
## Indicators of Compromise
The report lists hashes for samples encountered during the monitoring period:
- **File indicators:**
- `1fe046d8b5e52d23adf111d6a2ce8fd0`
- `3438330338936c52ccadbcc00ad8eb70`
- `3c69845de1a804055d0c2de3651de270`
- `7bf371744441119363b88368c21f30d7`
- `7ffb8a403a298e5b0d5f8bf3c6d119e6`
- **Network indicators:** *None defanged provided in summary.*
- **Behavioral indicators:** Increase in new ransomware samples collected compared to March.
## Response Actions
Response actions are limited to *analytical* measures identified in the report:
- **Containment measures:** *Not specified.*
- **Eradication steps:** *Not specified.*
- **Recovery actions:** *Not specified.*
*(Note: The primary response described is ongoing threat intelligence collection and statistical analysis via ATIP/AhnLab TIP.)*
## Lessons Learned
- The volume of new ransomware samples collected increased in April compared to March, indicating sustained threat activity.
- Reliance on DLS monitoring is a key method for identifying which organizations have suffered successful data exfiltration.
- The data is incomplete as some groups' information was collected late or not at all.
## Recommendations
- **Prevention measures for similar incidents:** Proactive signature/behavioral monitoring (as implemented by AhnLab) remains crucial for identifying novel and evolving ransomware samples.
- Organizations targeted by these groups should ensure backups are isolated and tested, and external communication plans address DLS postings.