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Incident

TalkTalk Group

Incident posture

Attack window
Oct 2015
Location
United Kingdom
Status
Historical
CIA posture
Available to members
Updated
2026-01-13 16:36

Linked entities

Victim
TalkTalk Group
Threat actors
0 actors
Sources
1 source

Timeline

Occurred
Oct 2015
Discovered
Pending
Disclosed
Pending
Resolved
Pending

Summary

A UK telecommunications provider suffered a significant cyberattack compromising up to 1.2 million customer email addresses, names, phone numbers, and 21,000 bank account details, though financial data accessed was incomplete and unusable for transactions. Multiple suspects, including minors, were arrested and released on bail, while the company notified affected customers and advised password changes amid warnings about potential fraud attempts.

Motives

Detailed motive labels are available to members.

2 motives

TTPs

Detailed technique labels are available to members.

1 technique

Description

In October 2015, UK telecommunications provider TalkTalk experienced a significant cyberattack on its website, leading to unauthorized access of customer data. Police arrested four individuals in connection with the incident: a 16-year-old boy in Norwich, another 16-year-old in London, a 15-year-old in County Antrim, Northern Ireland, and a 20-year-old man from Staffordshire. All suspects were released on bail by October 23, 2015, with the Norwich teenager scheduled to return in March for further investigation. The attack compromised personal information including email addresses, names, and phone numbers for up to 1.2 million customers, along with 21,000 unique bank account numbers and sort codes. TalkTalk initially believed the breach was more extensive but later confirmed these reduced figures. The company clarified that any accessed credit or debit card details were incomplete and could not facilitate fraudulent transactions due to missing critical information.

TalkTalk responded by advising its four million UK customers to change account passwords once its website resumed normal operations, specifically warning against reusing compromised credentials across other services. The company issued explicit warnings about potential phishing attempts, stating it would never contact customers to request bank details, passwords, or software installations. All affected customers were promised written notifications detailing exactly which information had been accessed in the breach. While emphasizing the incomplete nature of the stolen financial data, TalkTalk urged customers to monitor accounts for suspicious activity. The incident prompted ongoing police investigations under the Computer Misuse Act, with law enforcement executing property searches in connection with the arrests.

Sources

Sources available to members: 1 source.

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