Was mengseng.com hit by ransomware?

mengseng.com was listed by the lockbit5 ransomware operation (Thailand), and stolen data was published on the group's leak site. Darkfield tracks this disclosure with the original leak post, screenshot and group context.

Who is the lockbit5 ransomware group?

lockbit5 is a ransomware operator tracked by Darkfield. See the full operator dossier for its known victims, sectors targeted, IOCs and leak-site infrastructure.

What data was leaked in the mengseng.com breach?

lockbit5 published data attributed to mengseng.com. Darkfield captured the leak post and a screenshot of the listing.

Ransomware victim disclosure

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Meng Seng Plastic Co., Ltd.

listed as mengseng.com · Claimed by Lockbit5 · listed 4 months ago

Age

since listed · data leaked

Status timeline

ListedFeb 23, 2026
Data leakeddate unknown

At a glance

Group: Lockbit5
Status: Data leaked
Country: Thailand
Listed on leak site: Feb 23, 2026

About the victim

AI dossier — public-source company profile

Meng Seng Plastic Co., Ltd. is a Thai manufacturer specializing in comprehensive plastic packaging solutions, including cosmetic packaging and pharmaceutical packaging. The company operates a full-service production facility and markets itself as a one-stop plastic packaging manufacturer. Its website is published in Thai, indicating primary operations in Thailand.

Industry: Plastic Packaging Manufacturing

Attack summary

Severity: high — Data has been confirmed as published by the threat actor, indicating successful exfiltration of business data from a manufacturing company; while the data type is not confirmed as regulated/sensitive at scale, publication of exfiltrated data elevates severity to high.

LockBit 5 claims to have attacked Meng Seng Plastic Co., Ltd. and has published data (disclosed status: data_published), indicating exfiltration of company data; no ransom amount was stated and no specific data volume was disclosed.

high

Data the group says was taken

AI dossier — extracted from the leak post

Company internal files
Business documents

What the group claims

Meng Seng Plastic Co., Ltd. is a comprehensive manufacturer of plastic packaging, specializing in co...

Sources

Victim sitemengseng.com
Leak posthttp://lockbitapt67g6rwzjbcxnww5efpg4qok6vpfeth7wx3okj52ks4wtad.onion/post/872a69c011e339a711d7176d133fe0f4

Source

Indexed 4 months ago

This page surfaces a public ransomware disclosure indexed by Darkfield. Original posts come from the operator's own leak site; we cross-check against ransomware.live, RansomLook and RansomWatch where applicable. Share this URL freely.

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Disclosure context

About lockbit5

Based on the provided data, LockBit5 appears to be a recently emerged ransomware operation first observed in December 2025, representing what may be a new iteration or rebrand within the LockBit ransomware ecosystem, with primary financial motivations evidenced by their targeting of high-value sectors. Given the LockBit naming convention and the timing of emergence, this group likely operates from Eastern Europe or Russia and may represent either a continuation of previous LockBit operations or a new affiliate group leveraging the established LockBit brand, though specific organizational details remain undocumented by major security agencies. While detailed attack methodologies have not been publicly documented by CISA, FBI, or major security researchers, the group's targeting pattern across 157 victims suggests a broad-spectrum approach focusing on technology, manufacturing, healthcare, and transportation sectors primarily in the United States, Brazil, Germany, Italy, and Mexico. Due to the group's recent emergence in December 2025, there are no publicly documented notable campaigns or major incidents reported by established threat intelligence sources, though the victim count indicates active operations. The group appears to be currently active based on the recent first observation date, though comprehensive analysis from major security agencies has not yet been published given the short timeframe since emergence. The group has been linked to 278 public disclosures across our corpus. First observed on a leak site on December 7, 2025; most recent post June 11, 2026. The operation is currently active.

Timeline of this disclosure

February 23, 2026mengseng.com listed by lockbit5on the group's public leak site

Other recent disclosures by lockbit5

lockbit5 has been linked to 278 public victims on Darkfield. A sample of the most recent:

See the full lockbit5 dossier →

Sector and geography

Geographically, mengseng.com is reported in Thailand, a country with 45 ransomware disclosures in our corpus.

If your organisation is affected

A listing by lockbit5 means mengseng.com appeared on a ransomware extortion site and data attributed to it has been published. If this is your organisation, or a supplier you depend on, the priority is to confirm the intrusion and contain it before the window to act closes.

Engage your incident-response team and preserve forensic evidence before remediating — do not wipe affected systems first.
Force a password reset and revoke active sessions for exposed accounts; rotate any credentials, API keys or certificates that may have been in the stolen data.
Assess regulatory notification duties (GDPR, NIS2, sector regulators) — many carry a 72-hour reporting clock from awareness.
Monitor for the data appearing on lockbit5's leak site and across paste and breach channels, and brief downstream partners who may be exposed through you.

How we know this. Darkfield monitors public ransomware leak sites continuously, archiving every new disclosure and the data later released against the victim. Each entry on this page is sourced from the operator's own publication and cross-checked against complementary OSINT feeds (RansomLook, ransomware.live, RansomWatch). We do not collect or host stolen data — only the metadata, timestamps and screenshots needed to make the public disclosure searchable and accountable. Records here are corrected when the original post is edited, retracted, or merged with another disclosure.