關於 payload data ，我們在網路上蒐集到這些相關的討論、資訊與評價

OSSLab Geek Lab解讀一下最近鬧的滿城風雨的公民實驗室的Zoom安全報告
這是篇非常棒的如何拆解加密封包還原視訊跟音訊資安文...
1. H.264視訊碼流最小單位為NALU
一個NALU = 一組對應於視頻編碼的NALU頭部信息+ 一個原始字節序列負荷(RBSP,Raw Byte Sequence Payload).
這邊nal_unit_type都為0 ,無法判定類型.
不過最後有分析出NAL Payload有後面數據大小,為data slice解密後,組合後為H.264 video stream.

2.對電腦DRAM 做數位鑑識,發現名為conf.skey此為AES 128 key 全部使用者跟會議內容都用此key加密傳送跟接收後解密.

3.錄到封包後,要考慮到一個client都用同個SSRC,另外用時間戳組來拼順序,用key解密再組合成完整視訊raw檔案.

4.音訊一樣加密,推測用啥音訊codec ,是利用RTP間隔時間戳相隔多大來判定.640所以應該為Silk16 codec.

5.在Linux版本Zoom設定proxy上設為自建的mitmproxy, 會報警告說未驗證.從mitmproxy也可得到密鑰AES-128 conf.skey

6.測試中發現在加拿大跟美國通訊用戶 AES-key 是由52.81.151.250位於北京Server配送的
因此最終懷疑,確實有可能.若中國政府要求可取得此密鑰若有測錄封包就可解密還原內容.

7.最後Zoom官方的回應是
中國以外的用戶,會立即將中國大陸的數據中心從服務器中刪除。

圖片引用
UniHub 有你好棒
參考

https://citizenlab.ca/2020/04/move-fast-roll-your-own-crypto-a-quick-look-at-the-confidentiality-of-zoom-meetings/

http://0rz.tw/HOiaK

https://commons.erau.edu/cgi/viewcontent.cgi?article=1174&context=jdfsl

http://blog.gitdns.org/2017/03/14/h264/

#OSSLab #數位鑑識 #拜託國家訂的資安檢測要這樣水準

ใหม่ ฝาท้ายกระบะสุดล้ำ Multi-Flex Tailgate ที่ใช้ใน The new 2021 CHEVROLET SILVERADO 1500 โฉมใหม่ล่าสุด

DETROIT — The 2021 Chevrolet Silverado 1500 offers a truckload of new mechanical and technological updates, including the addition of an available Multi-Flex Tailgate, impressive trailering capacity and enhanced tech.

Increased Tailgate and Bed Functionality
The Multi-Flex Tailgate offers Silverado customers six unique functions, allowing for easier access to bed cargo, enhanced loading solutions and a standing workstation. With a weight capacity of 375 pounds (170 kg), different configurations for the Multi-Flex Tailgate activate using a key fob or two tailgate-mounted buttons, one for the full gate and another for the second-tier loading and storage options. Combined with the Silverado Durabed – featuring impressive cargo space, LED lighting, a 120-volt outlet and 12 fixed tie-downs – Multi-Flex makes the 2021 model the most functional and capable Silverado ever. The Multi-Flex Tailgate will be available in early 2021 on all new Silverado 1500 models.

Improved Trailering Capability on Silverado’s Most Efficient Engine Options
Chevrolet has long been one of the leaders in trailering, providing the power and the technology to instill customer confidence while towing1. The 2021 Silverado will feature increased conventional trailering capability for two of its most efficient engines, compared to the 2020 model year.

The 2.7L Turbo adds thousands of pounds of trailering capacity to every configuration. The popular Crew Cab Short Box model increases its rating by 2,500 pounds to a max capacity of 9,300 pounds in two-wheel drive. A newly available Regular Cab Long Box model provides the maximum 2.7L tow rating of 9,600 pounds and ups Silverado’s overall max payload to 2,280 pounds in 2WD.

The 3.0L Duramax turbo-diesel adds an additional 1,900 pounds of trailering capacity to nearly every configuration and provides the maximum capacity of 9,500 pounds to 2WD models. The 3.0L Duramax engine also receives a $1,500 MSRP price reduction for 2021 models, so customers benefit from both increased towing capacity and industry-leading EPA-estimated fuel economy of 33 mpg highway in 2WD at a great value.

Chevrolet is confident these engines meet or exceed most trailering needs, as 96 percent of light-duty pickup owners tow less than 10,000 pounds, according to data from MaritzCX an InMoment Company. Additional testing and validation revealed the 2.7L Turbo possesses better-than-expected cooling performance, while the 3.0L Duramax improvements are attributed to the better-than-expected rear axle durability. Chevrolet engineers recertified both engines to the SAE J2807 standard with impressive results.