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Jul 26, 2021
PetitPotam NTLM Relay Attack
THE THREAT PetitPotam is a variant of NTLM Relay attacks discovered by security researcher Gilles Lionel. Proof of Concept code released last week [1] relies on the Encrypting File System Remote (EFSRPC) protocol to provoke a Windows host into performing an NTLM authentication request against an attacker-controlled server, exposing NTLM authentication details or authentication certificates.…
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Tecala and eSentire Partner to Protect Enterprises across APAC from Business-Disrupting Cyber Attacks
Sydney, 12 July, 2021 - Tecala, Australia’s award-winning technology services and IT consulting provider, today announced it has chosen eSentire, the global Authority in Managed Detection and Response (MDR) cybersecurity services, as their exclusive MDR solution provider in Australia and New Zealand. This partnership will enable Tecala to augment its cybersecurity practice and offer enterprises…
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Security advisories — Jul 20, 2021

CVE-2021-33909 - Linux LPE Vulnerability

2 min read

THE THREAT

Security researchers from Qualys have announced a Local Privilege Escalation (LPE) vulnerability impacting the Linux operating system. The vulnerability is tracked as CVE-2021-33909 and has been alternatively named Sequoia. Exploitation would allow a threat actor with previous access to a vulnerable system to run code with root privileges. Proof-of-Concept (PoC) exploit code is publicly available; at this time the exploit code only allows for denial-of-service, but it is expected to be modified for LPE in the near future.

The Sequoia vulnerability has been confirmed to impact Debian, Ubuntu, and Fedora; other Linux distributions are likely vulnerable but have not been confirmed at this point. Organizations are strongly recommended to apply security patches as they are released by individual Linux distributions.

What we’re doing about it

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Additional information

Exploitation of CVE-2021-33909 has not been identified in the wild at this time. Exploitation is expected in the near future, as PoC code is publicly available, reducing the barriers of exploitation for threat actors.

Qualys has tested the exploit against installations of Ubuntu 20.04, Ubuntu 20.10, Ubuntu 21.04, Debian 11, and Fedora 34 Workstation. It is highly likely that other Linux distributions are impacted.

Qualys has released two mitigations for CVE-2021-33909. Despite mitigations, the primary recommendation is for organizations to apply the relevant security patches as soon as possible. It should be noted that both of the following mitigations may be bypassed.

References:

[1] https://www.qualys.com/2021/07/20/cve-2021-33909/sequoia-local-privilege-escalation-linux.txt