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De-a lungul timpului am observat foarte des intrebarea: “Cum sa incep cu domeniul security?”. Exista atat persoane la inceput de drum care isi doresc o cariera pe aceasta cale cat si persoane cu experienta in domeniul IT dornice sa inteleaga ce presupune acest domeniu. Voi incerca sa raspund acestei intrebari din perspectiva personala, oferind sugestii celor care nu stiu cu ce sa inceapa si cum sa porneasca pe acest drum.

Have you considered that in certain situations the way hackers exploit vulnerabilities over the network can be predictable? Anyone with access to encrypted traffic can reverse the logic behind the exploit and thus obtain the same data as the exploit. Various automated tools have been analyzed and it has been found that these tools operate in an unsafe way. Various exploit databases were analyzed and we learned that some of these are written in an insecure (predictable) way. This presentation will showcase the results of the research, including examples of exploits that once executed can be harmful. The data we obtain after exploitation can be accessible to other entities without the need of decrypting the traffic. The SSL/TLS specs will not change. There is a clear reason for that and in this presentation I will argue this, but what will change for sure is the way hackers will write some of the exploits.

Adica s-a rupt receiverul de la tastatura. Microsoft All-In-One este RF (Wireless), nicidecum Bluetooth. Nu iti va functiona cu niciun alt receiver wireless pentru ca vin special facute asa (fiecare dongle functioneaza doar cu tastatura din acel set).

How to protect RDP Posted: March 18, 2022 by Pieter Arntz You didn’t really think that the ransomware wave was coming to an end, did you? You may be tempted to think so, given the decline in reports about massive ransomware campaigns. Don’t be fooled. Over the last five years, one of the primary attack vectors for ransomware attacks has been the Remote Desktop Protocol (RDP). Remote desktop is exactly what the name implies, a tool for remotely controlling a PC that gives you all the power and control you would have if you were actually sitting behind it—which is what makes it so dangerous in the wrong hands. Bruce-force attacks Threat actors use brute-force password guessing attacks to find RDP login credentials. These attacks use computer programs that will try password after password until they guess one correctly, or run out of passwords. The passwords they guess can be sold via criminal markets to ransomware gangs that use them to breach their victims’ networks. Once they have RDP access, ransomware gangs can deploy specialized tools to: Elevate their privileges (when needed) Leave backdoors for future use Gain control over wider parts of the infiltrated network Deploy ransomware and leave payment instructions The first three steps are most important for businesses to pay attention to, as they need to be examined after a breach has been noticed. The easiest and cheapest way to stop a ransomware attack is to prevent the initial breach of the target, and in many cases that means locking down RDP. Securing RDP If you want to deploy software to remotely operate your work computers, RDP is essentially a safe and easy-to-use protocol, with a client that comes pre-installed on Windows systems and is also available for other operating systems. There are a few things you can do to make it a lot harder to gain access to your network over unauthorized RDP connections: Decide if you really need RDP. This is an important question and you should not be afraid to ask it. Even if you are hardened against brute-force attacks, there is always the chance that attackers will find a remote vulnerability in RDP and exploit it. Before you enable RDP for anyone, be sure that you need it. Limit access to the users who need it. Reduce the number of opportunities an attacker has to guess a weak password by following the principle of least privilege. This cannot be done from the Remote Desktop settings but requires security policies. We have included a guide on how to do this later in this article. Limit access to specific IP addresses. This is another form of following the principle of least privilege. There is simply no need for many IP addresses to have access to your RDP clients. Rather than banning the IP addresses that don’t need access, allow only those that do. Use strong passwords. Even the most persistent attacker will only ever guess very weak passwords because it is more cost effective to make a few guesses on a lot of computers than it is to make lots of guesses on one. So the first and most basic form of defence is to have users choose even moderately strong passwords—meaning passwords that don’t appear in lists of the most commonly used passwords, and aren’t based on dictionary words. Of course, getting users to actually do that is notoriously difficult, so you need to use other hardening measures as well. Use rate limiting. Rate limiting (such as Malwarebytes Brute Force Protection) has the effect of significantly strengthening the defenses of weak passwords. It works by reducing the speed at which attackers can make login attempts, typically by shutting them out for a period of time after a small number of incorrect guesses. This represents a huge barrier for a computer program looking to race through tens or even hundreds of thousands of password attempts. Use multi-factor authentication (MFA). MFA can stop password guessing in its tracks but it can be difficult to roll out and support. Any second authentication factor will make attacks significantly more difficult, but factors that don’t require user interaction—such as hardware keys and client certificates—are the most robust. Put RDP behind a VPN. Forcing users to connect to a VPN before they can log in to RDP effectively takes RDP off the Internet and away from password guessing attacks. This can be extremely effective but it comes at the cost of maintaining a VPN, and simply shifts the burden of securing your users’ point of access from RDP to the VPN. Diligent patching is essential. In the last few years ransomware gangs and other cybercriminals have made extensive use of vulnerabilities in popular, corporate VPNs. Use a Remote Desktop Gateway Server. This provides additional security and operational benefits, like MFA. The logs it takes of RDP sessions can prove very useful if you find yourself trying to figure out what might have happened after a breach. Because the logs are not on the compromised machine, they are harder for intruders to modify or delete. Do not disable Network Level Authentication (NLA). NLA offers an extra authentication level. Enable it, if it wasn’t already. Other things that might help The things in the list below aren’t effective enough to constitute genuine hardening, but might help reduce the volume of attacks you see. They are easy to do but they are not a substitute for the list above. Changing the RDP port. Some hardening guides recommend changing the RDP port so that it does not use the default port number, 3389. Although this might reduce the number of scans that find your RDP clients, our research suggests that plenty of attackers will still find you. Retire the Administrator username. Although some password guessing attacks use a variety of usernames, including automatically generated ones, many of them simply try to guess the password for the user named Administrator (or the local equivalent). However, because usernames are not treated as secrets by either users or systems, unlike passwords, you should not rely on the obscurity of your usernames to protect you. Limiting access to the users that need it The first step in this process is to create a user group that will be allowed remote access. You can do this in the Group Policy Management Console (GPMC.MSC). In this console, select Computer Configuration > Windows Settings > Security Settings > Restricted Groups. Right-click Restricted Groups and then click Add Group. Click Browse > type Remote > click Check Names and you should see “REMOTE DESKTOP USERS.” Click OK in the Add Groups dialog. Click Add beside the MEMBERS OF THIS GROUP box and click Browse. Type the name of the domain group, then click Check Names > click OK > OK. On the PC, run an elevated command prompt and type GPUPDATE/FORCE to refresh the GPolicy. You should see the group added under the SELECT USERS button on the REMOTE tab of the PC’s SYSTEM PROPERTIES. Now you can open the related local policies by opening Control Panel > System and Security > Administrative Tools > Local Security Policy > User Rights Assignment. Remove the “Administrators” group from the “Allow log on through Remote Desktop Services” policy and certainly do not grant access to the account with the username “Administrator.” That account is perfect for the intruders—they would love to take it over. Also remove the “Remote Desktop Users Group” as contradictory as that may seem. Because by default, the user group “Everyone” is a member of the “Remote Desktop Users” group. Now, add the user(s) that you specifically want to have remote access to this system, and make sure that they have the rights they need—but nothing more. Restrict the actions they can perform to limit the damage that they can do if the account should ever become compromised. Secure your network resources In the context of RDP attacks, it is also important that you apply some internal safety measures. PCs that can be used remotely should be able to use network resources, but not be able to destroy them. Use restrictive policies to keep the possible damage at bay that any user, not just a remote one, can do. Aftermath of an attack If you have been impacted by a ransomware attack via RDP, you’ll need to take some steps to better secure your network and endpoints. After you have recovered your files from a backup or by forking over the ransom, you need to check your systems for any changes the attackers have made that would make a future visit easier for them—especially if you decided to pay the ransom. By paying the threat actors, you have essentially painted a bulls-eye on your own back. You are now a desirable target, because they know you will pay to get your files back, if necessary. To be sure there are no artifacts left behind, check the computer that was used to access the network via RDP for Trojans and hacking tools, and also any networked devices that could have been accessed from the compromised machine. Sursa: https://blog.malwarebytes.com/security-world/business-security-world/2022/03/protect-rdp-access-ransomware-attacks/

Multumim tuturor care au participat la concursul CTF! De asemenea multumim tuturor celor care au creat exercitii! Clasamentul final poate fi vazut aici: https://ctf.rstcon.com/scoreboard - Locul I - adragos (3000 RON) - Locul II - Kayn (2000 RON) - Locul III - edmund (1000 RON) Castigatorii au fost contactati pentru oferirea premiilor. Exercitiile CTF vor mai ramane online o perioada (1-2 saptamani): https://ctf.rstcon.com/ Mentionez ca exercitiul Windows PWN nu a fost rezolvat, prima persoana care o va rezolva va primi un premiu bonus de 1000 RON. Statistici: - 78 de persoane inregistrate - 32 au rezolvat cel putin un exercitiu - 25 au rezolvat probabil cel mai usor exercitiu (Steago) Asteptam parerile voastre referitoare la CTF dar si la exercitii. De asemenea sper ca la anul sa avem mai multi participanti si mai multe exercitii.

Asa cum e indicat si aici, eu il pun in spate la un VPN. Blocat pt public prin Firewall, lasat doar Private si pt Domain. Daca cineva vrea sa faca pasii de mai sus pe PC-ul propriu din whatever reason, sa ajungeti la Group Policy folositi "gpedit.msc", "GPMC.MSC" e doar pentru servere care au AD (sunt Domain Controllers).

O sa exploram impreuna viata unui blue-teamer. O sa vedem exemple despre cum nimic nu e niciodata sigur, despre cursa de-a soarecele si pisica intre blue-team si atackatori dar si despre cum userii gasesc mereu cate ceva nou si interesant care strica planurile de securitate ale unei firme.

Pe parcursul prezentarii, vom aborda o tema ce se invarte mai mult in jurul Red Teaming-ului, ci anume – BadUSB. Ce este, cum il putem folosi, cateva real-life use case-uri, payload development, si bypass-uri cu acesta (UAC, CLM, AMSI, etc.).

Acest studiu se concentreaza pe analizarea unui exploit recent publicat in luna Ianuarie 2022 ce afecteaza componenta de sistem win32k din Windows kernel si rezulta intr-o vulnerabilitate de tipul elevare de privilegii. Analiza exploiturilor de tipul 1day ne poate ajuta atat pe plan defensiv, prin crearea de detectii relevante asupra celor mai noi tehnicilor de exploatare, cat si in identificare si prevenirea unor noi vulnerabilitati similare in aceleasi componente. Totodata, cercetarea acestui CVE reprezinta un bun exemplu in care patch-urile aplicate initial nu mitigheaza in profunzime problema. In cadrul prezentarii, vom discuta despre notiuni de Windows internals, atacuri de tip data-only, WinDbg kernel debugging si indicatori de detectie, cu un focus principal pe analiza defensiva si intelegerea procesului de exploatare.

Prezentarile video sunt disponibile pe site: https://rstcon.com/prezentari/ Le puteti accesa direct de pe canalul de Youtube: https://www.youtube.com/channel/UCs-oJJm7A4VmwBtezIOn0JQ Si exista si un playlist RSTCon #2: https://www.youtube.com/watch?v=MTYdX2hGVXY&list=PLTaLvwriPW8zi3pkblN8yAqbZDZur992d

Trebuie sa se alinieze astrele ca sa poata fi folosita vulnerabilitatea. Mare parte din aplicatiile care genereaza PDF-uri iau totul din baza de date. Singura chestie unde as vedea asta e intr-o aplicatie care iti pune semnatura pe un PDF existent generat tot prin dompdf, asta in cazul in care cine a facut aplicatia nu a stiut sa puna validare pe input, macar ceva de genul ^[a-zA-Z -]{6,50}$ O alternativa buna, folosita, testata la dompdf e tcpdf. Face minuni pe shared hosting.

Programele pe care le gasiti aici sunt postate de catre utilizatori si in general nu trec printr-o verificare preliminara. Ruland pe computerul personal un executabil descarcat de la aceasta rubrica va expuneti riscului de a va fi furate parolele cu care va logati pe conturile personale, de a va fi accesate fisierele fara voia voastra sau puteti deveni parte a unui botnet folosit la spam, flood, socksuri etc. In toate aceste cazuri efectul este unul foarte neplacut. Pentru a rula aceste programe fara a risca sa va compromiteti conturile puteti folosi o solutie de virtualizare ca: VMWare, VirtualBox, VirtualPC. Va recomandam ca in cazul in care linkul de download este un site de file sharing sa cautati cu ajutorul Google sursa originala de download a programului daca aceasta exista. In cazul in care gasiti un site oficial al unui program postat aici, iar in topic este pus un link de download de pe un site de filesharing aveti dreptul sa postati in acel topic o cerere pentru a fi schimbat linkul cu cel al site-ului oficial. Daca linkul nu va fi schimbat in urmatoarele 12 ore puteti contacta un membru al staffului pentru a cere inlocuirea linkului. Pentru cei care posteaza: folositi linkurile oficiale de download daca acestea exista! P.S.: Raportati linkurile cu survey!