Monday , June 23 2025

Microsoft Teams exploiting tool on GitHub, What Microsoft say?

A new tool is available on GitHub that gives attackers a way to leverage a recently disclosed vulnerability in Microsoft Teams and automatically deliver malicious files to targeted Teams users in an organization.

The tool, dubbed “TeamsPhisher,” works in environments where an organization allows communications between its internal Teams users and external Teams users — or tenants. It allows attackers to deliver payloads directly into a victim’s inbox without relying on a traditional phishing or social engineering scams to get it there.

Hackers Bypass Gmail MFA With App-Specific Password Reuse

A hacking group reportedly linked to Russian government has been discovered using a new phishing method that bypasses two-factor authentication...
Read More
Hackers Bypass Gmail MFA With App-Specific Password Reuse

Russia detects first SuperCard malware attacks via NFC

Russian cybersecurity experts discovered the first local data theft attacks using a modified version of legitimate near field communication (NFC)...
Read More
Russia detects first SuperCard malware attacks via NFC

Income Property Investments exposes 170,000+ Individuals record

Cybersecurity researcher Jeremiah Fowler discovered an unsecured database with 170,360 records belonging to a real estate company. It contained personal...
Read More
Income Property Investments exposes 170,000+ Individuals record

ALERT (CVE: 2023-28771)
Zyxel Firewalls Under Attack via CVE-2023-28771 by 244 IPs

GreyNoise found attempts to exploit CVE-2023-28771, a vulnerability in Zyxel's IKE affecting UDP port 500. The attack centers around CVE-2023-28771,...
Read More
ALERT (CVE: 2023-28771)  Zyxel Firewalls Under Attack via CVE-2023-28771 by 244 IPs

CISA Flags Active Exploits in Apple iOS and TP-Link Routers

The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has recently included two high-risk vulnerabilities in its Known Exploited Vulnerabilities (KEV)...
Read More
CISA Flags Active Exploits in Apple iOS and TP-Link Routers

10K Records Allegedly from Mac Cloud Provider’s Customers Leaked Online

SafetyDetectives’ Cybersecurity Team discovered a public post on a clear web forum in which a threat actor claimed to have...
Read More
10K Records Allegedly from Mac Cloud Provider’s Customers Leaked Online

Canada 2nd largest airlines “WestJet” investigates cyberattack disrupting internal systems

WestJet, Canada's second-largest airline, is looking into a cyberattack that has affected some internal systems during its response to the...
Read More
Canada 2nd largest airlines “WestJet” investigates cyberattack disrupting internal systems

Paraguay 7.4 Million Citizen Records Leaked on Dark Web

Resecurity found 7.4 million records of Paraguayan citizens' personal information leaked on the dark web today. Last week, cybercriminals attempted...
Read More
Paraguay 7.4 Million Citizen Records Leaked on Dark Web

High-Severity Flaw in HashiCorp Nomad Allows Privilege Escalation

HashiCorp has revealed a critical vulnerability in its Nomad tool that may let attackers gain higher privileges by misusing the...
Read More
High-Severity Flaw in HashiCorp Nomad Allows Privilege Escalation

SoftBank: Over 137,000 personal info leaked

SoftBank has disclosed that personal information of more than 137,000 mobile subscribers—covering names, addresses, and phone numbers—might have been leaked...
Read More
SoftBank: Over 137,000 personal info leaked

“Give TeamsPhisher an attachment, a message, and a list of target Teams users,” said the tool’s developer Alex Reid, a member of the US Navy’s Red Team, in a description of the tool on GitHub. “It will upload the attachment to the sender’s Sharepoint and then iterate through the list of targets.”

ALSO READ:

Policy changed, Google now use your data for AI training

A member of the U.S. Navy’s red team has published the tool called TeamsPhisher that exploits a security issue in Microsoft Teams to bypass restrictions on incoming files from external tenants.

The tool works by tricking the client-side protections of Microsoft Teams into treating an external user as an internal one. This is possible because the application has a bug that allows the ID in the POST request of a message to be changed.

The tool was developed by Max Corbridge and Tom Ellson of UK-based security services company Jumpsec, who highlighted the problem last month. They explained that an attacker could use this bug to easily deliver malware to users in a targeted organization.

A Microsoft spokesperson has sent the following comment to media:

‘We’re aware of this report and have determined that it relies on social engineering to be successful. We encourage customers to practice good computing habits online, including exercising caution when clicking on links to web pages, opening unknown files, or accepting file transfers’.

According to GitHub, TeamsPhisher is a Python3 program that facilitates the delivery of phishing messages and attachments to Microsoft Teams users whose organizations allow external communications.

It is not ordinarily possible to send files to Teams users outside one’s organization. Max Corbridge (@CorbridgeMax) and Tom Ellson (@tde_sec) over at JUMPSEC recently disclosed a way to get around this restriction by manipulating Teams web requests in order to alter the recipient of a message with an attached file.

TeamsPhisher incorporates this technique in addition to some earlier ones disclosed by Andrea Santese (@Medu554). It also heavily leans upon TeamsEnum, a fantastic piece of work from Bastian Kanbach (@bka) of SSE, for the authentication part of the attack flow as well as some general helper functions.

Check Also

HashiCorp

High-Severity Flaw in HashiCorp Nomad Allows Privilege Escalation

HashiCorp has revealed a critical vulnerability in its Nomad tool that may let attackers gain …

Leave a Reply

Your email address will not be published. Required fields are marked *