Entries Tagged "firewall"

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Backdoor in Zyxel Firewalls and Gateways

This is bad:

More than 100,000 Zyxel firewalls, VPN gateways, and access point controllers contain a hardcoded admin-level backdoor account that can grant attackers root access to devices via either the SSH interface or the web administration panel.


Installing patches removes the backdoor account, which, according to Eye Control researchers, uses the “zyfwp” username and the “PrOw!aN_fXp” password.

“The plaintext password was visible in one of the binaries on the system,” the Dutch researchers said in a report published before the Christmas 2020 holiday.

Posted on January 6, 2021 at 5:44 AMView Comments

Adding a Hardware Backdoor to a Networked Computer

Interesting proof of concept:

At the CS3sthlm security conference later this month, security researcher Monta Elkins will show how he created a proof-of-concept version of that hardware hack in his basement. He intends to demonstrate just how easily spies, criminals, or saboteurs with even minimal skills, working on a shoestring budget, can plant a chip in enterprise IT equipment to offer themselves stealthy backdoor access…. With only a $150 hot-air soldering tool, a $40 microscope, and some $2 chips ordered online, Elkins was able to alter a Cisco firewall in a way that he says most IT admins likely wouldn’t notice, yet would give a remote attacker deep control.

Posted on October 18, 2019 at 5:54 AMView Comments

Article from a Former Chinese PLA General on Cyber Sovereignty

Interesting article by Major General Hao Yeli, Chinese People’s Liberation Army (ret.), a senior advisor at the China International Institute for Strategic Society, Vice President of China Institute for Innovation and Development Strategy, and the Chair of the Guanchao Cyber Forum.

Against the background of globalization and the internet era, the emerging cyber sovereignty concept calls for breaking through the limitations of physical space and avoiding misunderstandings based on perceptions of binary opposition. Reinforcing a cyberspace community with a common destiny, it reconciles the tension between exclusivity and transferability, leading to a comprehensive perspective. China insists on its cyber sovereignty, meanwhile, it transfers segments of its cyber sovereignty reasonably. China rightly attaches importance to its national security, meanwhile, it promotes international cooperation and open development.

China has never been opposed to multi-party governance when appropriate, but rejects the denial of government’s proper role and responsibilities with respect to major issues. The multilateral and multiparty models are complementary rather than exclusive. Governments and multi-stakeholders can play different leading roles at the different levels of cyberspace.

In the internet era, the law of the jungle should give way to solidarity and shared responsibilities. Restricted connections should give way to openness and sharing. Intolerance should be replaced by understanding. And unilateral values should yield to respect for differences while recognizing the importance of diversity.

Posted on January 17, 2018 at 6:23 AMView Comments

NSA/GCHQ Exploits against Juniper Networking Equipment

The Intercept just published a 2011 GCHQ document outlining its exploit capabilities against Juniper networking equipment, including routers and NetScreen firewalls as part of this article.

GCHQ currently has capabilities against:

  • Juniper NetScreen Firewalls models Ns5gt, N25, NS50, NS500, NS204, NS208, NS5200, NS5000, SSG5, SSG20, SSG140, ISG 1000, ISG 2000. Some reverse engineering maybe required depending on firmware revisions.
  • Juniper Routers: M320 is currently being worked on and we would expect to have full support by the end of 2010.
  • No other models are currently supported.
  • Juniper technology sharing with NSA improved dramatically during CY2010 to exploit several target networks where GCHQ had access primacy.

Yes, the document said “end of 2010” even though the document is dated February 3, 2011.

This doesn’t have much to do with the Juniper backdoor currently in the news, but the document does provide even more evidence that (despite what the government says) the NSA hoards vulnerabilities in commonly used software for attack purposes instead of improving security for everyone by disclosing it.

Note: In case anyone is researching this issue, here is my complete list of useful links on various different aspects of the ongoing debate.

EDITED TO ADD: In thinking about the equities process, it’s worth differentiating among three different things: bugs, vulnerabilities, and exploits. Bugs are plentiful in code, but not all bugs can be turned into vulnerabilities. And not all vulnerabilities can be turned into exploits. Exploits are what matter; they’re what everyone uses to compromise our security. Fixing bugs and vulnerabilities is important because they could potentially be turned into exploits.

I think the US government deliberately clouds the issue when they say that they disclose almost all bugs they discover, ignoring the much more important question of how often they disclose exploits they discover. What this document shows is that — despite their insistence that they prioritize security over surveillance — they like to hoard exploits against commonly used network equipment.

Posted on December 28, 2015 at 6:54 AMView Comments

Back Door in Juniper Firewalls

Juniper has warned about a malicious back door in its firewalls that automatically decrypts VPN traffic. It’s been there for years.

Hopefully details are forthcoming, but the folks at Hacker News have pointed to this page about Juniper’s use of the DUAL_EC_DBRG random number generator. For those who don’t immediately recognize that name, it’s the pseudo-random-number generator that was backdoored by the NSA. Basically, the PRNG uses two secret parameters to create a public parameter, and anyone who knows those secret parameters can predict the output. In the standard, the NSA chose those parameters. Juniper doesn’t use those tainted parameters. Instead:

ScreenOS does make use of the Dual_EC_DRBG standard, but is designed to not use Dual_EC_DRBG as its primary random number generator. ScreenOS uses it in a way that should not be vulnerable to the possible issue that has been brought to light. Instead of using the NIST recommended curve points it uses self-generated basis points and then takes the output as an input to FIPS/ANSI X.9.31 PRNG, which is the random number generator used in ScreenOS cryptographic operations.

This means that all anyone has to do to break the PRNG is to hack into the firewall and copy or modify those “self-generated basis points.”

Here’s a good summary of what we know. The conclusion:

Again, assuming this hypothesis is correct then, if it wasn’t the NSA who did this, we have a case where a US government backdoor effort (Dual-EC) laid the groundwork for someone else to attack US interests. Certainly this attack would be a lot easier given the presence of a backdoor-friendly RNG already in place. And I’ve not even discussed the SSH backdoor which, as Wired notes, could have been the work of a different group entirely. That backdoor certainly isn’t NOBUS — Fox-IT claim to have found the backdoor password in six hours.

More details to come, I’m sure.

EDITED TO ADD (12/21): A technical overview of the SSH backdoor.

EDITED TO ADD (12/22): Matthew Green wrote a really good technical post about this.

They then piggybacked on top of it to build a backdoor of their own, something they were able to do because all of the hard work had already been done for them. The end result was a period in which someone — maybe a foreign government — was able to decrypt Juniper traffic in the U.S. and around the world. And all because Juniper had already paved the road.

Another good article.

Posted on December 21, 2015 at 6:52 AMView Comments

An Incredibly Insecure Voting Machine


The weak passwords — which are hard-coded and can’t be changed — were only one item on a long list of critical defects uncovered by the review. The Wi-Fi network the machines use is encrypted with wired equivalent privacy, an algorithm so weak that it takes as little as 10 minutes for attackers to break a network’s encryption key. The shortcomings of WEP have been so well-known that it was banished in 2004 by the IEEE, the world’s largest association of technical professionals. What’s more, the WINVote runs a version of Windows XP Embedded that hasn’t received a security patch since 2004, making it vulnerable to scores of known exploits that completely hijack the underlying machine. Making matters worse, the machine uses no firewall and exposes several important Internet ports.

It’s the AVS WinVote touchscreen Direct Recording Electronic (DRE). The Virginia Information Technology Agency (VITA) investigated the machine, and found that you could hack this machine from across the street with a smart phone:

So how would someone use these vulnerabilities to change an election?

  1. Take your laptop to a polling place, and sit outside in the parking lot.
  2. Use a free sniffer to capture the traffic, and use that to figure out the WEP password (which VITA did for us).
  3. Connect to the voting machine over WiFi.
  4. If asked for a password, the administrator password is “admin” (VITA provided that).
  5. Download the Microsoft Access database using Windows Explorer.
  6. Use a free tool to extract the hardwired key (“shoup”), which VITA also did for us.
  7. Use Microsoft Access to add, delete, or change any of the votes in the database.
  8. Upload the modified copy of the Microsoft Access database back to the voting machine.
  9. Wait for the election results to be published.

Note that none of the above steps, with the possible exception of figuring out the WEP password, require any technical expertise. In fact, they’re pretty much things that the average office worker does on a daily basis.


Posted on April 23, 2015 at 7:19 AMView Comments

HEADWATER: NSA Exploit of the Day

Today’s implant from the NSA’s Tailored Access Operations (TAO) group implant catalog:


(TS//SI//REL) HEADWATER is a Persistent Backdoor (PDB) software implant for selected Huawei routers. The implant will enable covert functions to be remotely executed within the router via an Internet connection.

(TS//SI//REL) HEADWATER PBD implant will be transferred remotely over the Internet to the selected target router by Remote Operations Center (ROC) personnel. After the transfer process is complete, the PBD will be installed in the router’s boot ROM via an upgrade command. The PBD will then be activated after a system reboot. Once activated, the ROC operators will be able to use DNT’s HAMMERMILL Insertion Tool (HIT) to control the PBD as it captures and examines all IP packets passing through the host router.

(TS//SI//REL) HEADWATER is the cover term for the PBD for Huawei Technologies routers. PBD has been adopted for use in the joint NSA/CIA effort to exploit Huawei network equipment. (The cover name for this joint project is TURBOPANDA.)

STATUS: (U//FOUO) On the shelf ready for deployment.

Page, with graphics, is here. General information about TAO and the catalog is here.

This one is interesting. It basically turns the router into an eavesdropping platform.

In the comments, feel free to discuss how the exploit works, how we might detect it, how it has probably been improved since the catalog entry in 2008, and so on.

Posted on January 14, 2014 at 2:10 PMView Comments

SOUFFLETROUGH: NSA Exploit of the Day

One of the top secret NSA documents published by Der Spiegel is a 50-page catalog of “implants” from the NSA’s Tailored Access Group. Because the individual implants are so varied and we saw so many at once, most of them were never discussed in the security community. (Also, the pages were images, which makes them harder to index and search.) To rectify this, I am publishing an exploit a day on my blog.

Today’s implant:


(TS//SI//REL) SOUFFLETROUGH is a BIOS persistence implant for Juniper SSG 500 and SSG 300 firewalls. It persists DNT’s BANANAGLEE software implant. SOUFFLETROUGH also has an advanced persistent back-door capability.

(TS//SI//REL) SOUFFLETROUGH is a BIOS persistence implant for Juniper SSG 500 and SSG 300 series firewalls (320M, 350M, 520, 550, 520M, 550M). It persists DNT’s BANANAGLEE software implant and modifies the Juniper firewall’s operating system (ScreenOS) at boot time. If BANANAGLEE support is not available for the booting operating system, it can install a Persistent Backdoor (PBD) designed to work with BANANAGLEE’s communications structure, so that full access can be reacquired at a later time. It takes advantage of Intel’s System Management Mode for enhanced reliability and covertness. The PDB is also able to beacon home, and is fully configurable.

(TS//SI//REL) A typical SOUFFLETROUGH deployment on a target firewall with an exfiltration path to the Remote Operations Center (ROC) is shown above. SOUFFLETROUGH is remotely upgradeable and is also remotely installable provided BANANAGLEE is already on the firewall of interest.

Status: (C//REL) Released. Has been deployed. There are no availability restrictions preventing ongoing deployments.

Unit Cost: $0

Page, with graphics, is here. General information about TAO and the catalog is here.

In the comments, feel free to discuss how the exploit works, how we might detect it, how it has probably been improved since the catalog entry in 2008, and so on.

Posted on January 13, 2014 at 2:45 PMView Comments

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Sidebar photo of Bruce Schneier by Joe MacInnis.