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Nov 22, 2021
Microsoft Exchange Vulnerability - CVE-2021-42321
THE THREAT eSentire has identified publicly available Proof-of-Concept (PoC) exploit code, for the critical Microsoft Exchange vulnerability CVE-2021-42321. CVE-2021-42321 was announced as part of Microsoft’s November Patch Tuesday release. Exploitation would allow a remote threat actor, with previous authentication, to execute code on vulnerable servers. Prior to the patch release, Microsoft…
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Oct 28, 2021
Telarus and eSentire Expand Partnership to Safeguard Enterprises Globally Against Business Disrupting Ransomware and Zero-Day Attacks
London, UK and Sydney, Australia– Oct. 28, 2021 - eSentire, recognized globally as the Authority in Managed Detection and Response (MDR), today announces the expansion of its partnership with Telarus, the largest privately-held distributor of business cloud infrastructure and contact centre services. Building on their mutual success across North America, Telarus will bring eSentire’s Managed…
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Security advisories — Feb 26, 2019

Mailsploit Email Spoofing

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A set of security bugs that allow spoofed emails to evade standard security measures have been identified. Security researchers dubbed the flaws ‘Mailsploit’. This form of attack allows malicious actors to insert a fake sender name into emails without detection by modern anti-spoofing tools. In selective instances, Mailsploit will also allow malicious code to be run on a victim’s device. There are currently 33 email clients vulnerable to this attack including Apple Mail, Outlook, and Mozilla Thunderbird; for a full list of vulnerable mail clients please see the link below [1]. At the time of publication, only eight client applications have released patches.

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Additional information

The Mailsploit security bugs allow attackers’ spoofed emails to bypass the anti-spoofing protocol DMARC. The attack is made possible due to improper sanitization of non-ASCII characters in the "From:" field. Some email applications when decoding Internet Message Headers only display strings up to the first null or newline character. This prevents the full email address from being displayed to the user. As such, attackers can insert a null character to obfuscate their real email.

For additional technical details see the link for the original vulnerability report below [2].

[1] https://docs.google.com/spreadsheets/d/1jkb_ZybbAoUA43K902lL-sB7c1HMQ78-fhQ8nowJCQk/htmlview?sle=true

[2] https://www.mailsploit.com/index

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