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CIA 老大告訴參議員,在加密系統裡放後門是可行的,因為沒有公司可以逃離美國魔掌

如同標題講的,CIA 老大 John Brennan 告訴參議員,因為實務上不存在「Non-US encryption」,所以強制任何要進入美國的企業使用美版帶有後門的加密系統是可行的:「Non-US encryption is 'theoretical,' claims CIA chief in backdoor debate」。

CIA director John Brennan told US senators they shouldn't worry about mandatory encryption backdoors hurting American businesses.

And that's because, according to Brennan, there's no one else for people to turn to: if they don't want to use US-based technology because it's been forced to use weakened cryptography, they'll be out of luck because non-American solutions are simply "theoretical."

這位腦袋已經壞掉了啊,你知道有個叫做 China,拼做 C-h-i-n-a 的經濟體系嗎... 然後中美共用同一套有後門的加密系統瞬間就會被一堆人打槍,如果真的發生,還有個歐盟... 而且這些事情只是促進以色列的安全系統加速脫離美國掌控啊?以色列才是目前資安的超級強國啊...

這世界上有太多已經不是掌握在美國的東西了啊...

在 Python 的 pip、Nodejs 的 npm、Ruby 的 RubyGems 上面放木馬研究?

在 Python 領域裡常用 pip 安裝軟體:

$ pip install reqeusts

或是:

$ sudo pip install reqeusts

其他的平台也大致類似於這樣的動作。而在「Typosquatting programming language package managers」這篇文章裡,作者用 typo 之類的方式列出可能的名稱,像是這樣的名稱:

$ sudo pip install reqeusts

然後在這三個平台上發動攻擊,上傳了數百個套件並且觀察:

All in all, I created over 200 such packages and equipped them with a small program and uploaded them over the course of several months. The idea is to add some code to the packages that is executed whenever the package is downloaded with the installing user rights.

而這是「成果」:

關於 Juniper ScreenOS 防火牆被放後門的研究

一樣是從 Bruce Schneier 那邊看到的:「Details about Juniper's Firewall Backdoor」,原始的研究連結在「Cryptology ePrint Archive: Report 2016/376」這邊。

ScreenOS 被放了兩個後門,一個是 SSH 的後門:

Reverse engineering of ScreenOS binaries revealed that the first of these vulnerabilities was a conventional back door in the SSH password checker.

另外一個是「Dual EC 的 Q 值」被放了後門,而「NIST 所制定的 Dual EC 的 Q 值」本身就是個後門,所以有人把這個後門又給換掉了:

The second is far more intriguing: a change to the Q parameter used by the Dual EC pseudorandom number generator. It is widely known that Dual EC has the unfortunate property that an attacker with the ability to choose Q can, from a small sample of the generator's output, predict all future outputs. In a 2013 public statement, Juniper noted the use of Dual EC but claimed that ScreenOS included countermeasures that neutralized this form of attack.

第二個後門更發現嚴重的問題,Juniper 所宣稱的反制措施根本沒被執行到:

In this work, we report the results of a thorough independent analysis of the ScreenOS randomness subsystem, as well as its interaction with the IKE VPN key establishment protocol. Due to apparent flaws in the code, Juniper's countermeasures against a Dual EC attack are never executed.

也因此團隊確認選定 Q 值的人可以輕易的成功攻擊 IPSec 流量:

Moreover, by comparing sequential versions of ScreenOS, we identify a cluster of additional changes that were introduced concurrently with the inclusion of Dual EC in a single 2008 release. Taken as a whole, these changes render the ScreenOS system vulnerable to passive exploitation by an attacker who selects Q. We demonstrate this by installing our own parameters, and showing that it is possible to passively decrypt a single IKE handshake and its associated VPN traffic in isolation without observing any other network traffic.

Linux Mint 網站被黑,ISO 被加料

Linux Mint 官方放出警告,通知使用者網站被黑以及 ISO 被加料的資安事件:「Beware of hacked ISOs if you downloaded Linux Mint on February 20th!」,開頭的說明:

Hackers made a modified Linux Mint ISO, with a backdoor in it, and managed to hack our website to point to it.

不幸中獎的人建議的步驟是先離線,然後備份資料,再用確認安全的 ISO image 重新安裝,並且修改各網站的密碼 (尤其是 mail,可以被拿來重設各種服務):

Put the computer offline.
Backup your personal data, if any.
Reinstall the OS or format the partition.
Change your passwords for sensitive websites (for your email in particular).

荷蘭政府捐贈五十萬歐元給 OpenSSL

在一堆政府想要立法放後門進系統的情況下,荷蘭政府則反對這樣的想法,並且決定捐贈五十萬歐元 (目前約五十四萬美金) 給 OpenSSL:「Dutch govt says no to backdoors, slides $540k into OpenSSL without breaking eye contact」:

The Dutch government has formally opposed the introduction of backdoors in encryption products.

A government position paper, published by the Ministry of Security and Justice on Monday and signed by the security and business ministers, concludes that "the government believes that it is currently not appropriate to adopt restrictive legal measures against the development, availability and use of encryption within the Netherlands."

以及:

The formal position comes just months after the Dutch government approved a €500,000 ($540,000) grant to OpenSSL, the project developing the widely used open-source encryption software library.

Mac OS X 的安全性漏洞:蘋果沒打算修 10.9 以下的版本...

在「Hidden backdoor API to root privileges in Apple OS X」這邊揭露了這個漏洞 (接近於後門的設計)。

10.10.3 修正了這個問題,但沒打算修 10.7.x 到 10.9.x 的版本:

Apple has now released OS X 10.10.3 where the issue is resolved. OS X 10.9.x and older remain vulnerable, since Apple decided not to patch these versions. We recommend that all users upgrade to 10.10.3.

從 2014 年十月發現回報,2015 年一月蘋果建立 CVE-2015-1130,到 2015 年四月才正式修復 10.10.x 的部份:「About the security content of OS X Yosemite v10.10.3 and Security Update 2015-004」。

靠靠,我不想升到 10.10 啊...

Cisco 會將硬體寄送到貨運商,以提高 NSA 攔截安裝後門的難度

在「To Avoid NSA Interception, Cisco Will Ship To Decoy Addresses」這篇看到的報導,出自「Cisco posts kit to empty houses to dodge NSA chop shops」這篇。

去年 Snowden 揭露的資料顯示 NSA 會攔截 Cisco 的硬體,並且在上面安裝後門再打包寄出:「Greenwald alleges NSA tampers with routers to plant backdoors」:

"The NSA routinely receives – or intercepts – routers, servers and other computer network devices being exported from the US before they are delivered to the international customers."

The agency then implants backdoor surveillance tools, repackages the devices with a factory seal and sends them on. The NSA thus gains access to entire networks and all their users.

不過 Cisco 的反應好慢,去年五月就有的消息,現在才提出改善方案。

改善的方法是寄送到集散地,再請人去拿。讓 NSA 之類的單位想要攔截的成本提高。

NSA 付錢給 RSA 放後門的事件...

Edward Snowden 再次丟出 NSA 內部文件,表示 NSA 付錢給 RSA 在演算法裡面放後門:「Exclusive: Secret contract tied NSA and security industry pioneer」。

RSA 的回應則是完全不想提到這筆錢是做什麼用的:「RSA Response to Media Claims Regarding NSA Relationship」。

現在一般在猜測,這個後門應該就是 RSA BSAFE 的預設偽隨機數產生器 Dual_EC_DRBG

對於 Dual_EC_DRBG 的攻擊,2006 年的「Cryptanalysis of the Dual Elliptic Curve Pseudorandom Generator」就這樣寫:

Our experimental results and also empirical argument show that the DEC PRG is insecure. The attack does not imply solving the ECDLP for the corresponding elliptic curve. The attack is very efficient.

在 2007 年,Bruce Schneier 寫了一篇「Did NSA Put a Secret Backdoor in New Encryption Standard?」,提到這個弱點並沒有大到使得這個演算法不堪用,但看了總是不爽:

Problems with Dual_EC_DRBG were first described in early 2006. The math is complicated, but the general point is that the random numbers it produces have a small bias. The problem isn't large enough to make the algorithm unusable -- and Appendix E of the NIST standard describes an optional work-around to avoid the issue -- but it's cause for concern. Cryptographers are a conservative bunch: We don't like to use algorithms that have even a whiff of a problem.

並且建議不要用 Dual_EC_DRBG:

My recommendation, if you're in need of a random-number generator, is not to use Dual_EC_DRBG under any circumstances. If you have to use something in SP 800-90, use CTR_DRBG or Hash_DRBG.

現在回頭看這件事情... hmmm...

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