{"uuid": "bf0e645e-6092-484f-9230-24a951412aa7", "vulnerability_lookup_origin": "1a89b78e-f703-45f3-bb86-59eb712668bd", "author": "9f56dd64-161d-43a6-b9c3-555944290a09", "vulnerability": "CVE-2021-4034", "type": "seen", "source": "https://t.me/hacking_Attack/41919", "content": "-IQtmRp5CEDRjOAWkQiDsltX4KbojtchvgTUzgl-nTuBIoBqcXE85Vunir8QYAq8GFLONQI9AkDzvjfMtE0FMmCubXnA0o79A=s16000 Attack vector: An attacker can create an environment variable and use this memory corruption technique to run his own executable named \u201cvalue.\u201d Hence, an attacker can use pre-existing environment variable privilege escalation methods to exploit this.DemonstrationA proof of concept for this vulnerability has been uploaded on github which can be found here. To run the attack, we simply need to clone the repository, make the executable and run it. The program will exploit this memory corruption weakness as explained above.cd /tmp\nmake\n./cve-2021-4034\nwhoami\ncat /etc/passwdhttps://blogger.googleusercontent.com/img/a/AVvXsEjWQ7pM_Bqk5j2m3mkyLI1KKRdXiFPtQc7Hh42-G6wwxYtDHFHZSDwdi6KFtP62KDNZFn7BLGdwhwQRfObiMwYjEPrFjm_hX3d69SjHy1mcT1BmpAs4Yh6-yh5A05cTwxJSGSQU2LsYHApdtMpinLYwlBQUlaxj9DAaSO5CO0fc71W1kOT4QlKV6cH-qQ=s16000 And just with two commands, we have exploited pkexec\u2019s vulnerability and escalated ourselves to root!Mitigation\u00b7 The vulnerability has already been patched by respective vendors. In Ubuntu 20.04 policykit-1 - 0.105-26ubuntu1.2 version mitigates this weakness.ConclusionAll of the unupdated older versions of Debian flavours and Red hat flavours are susceptible to this attack making it a severe risk for an organization. The ease of exploitation of this attack makes it even more dangerous. It is highly recommended that sys admins update their installed polkit packages today. Thanks for reading.___________________________ \n@hacking_Attack\n@Hacking_Video", "creation_timestamp": "2026-09-01T20:01:56.543074Z"}