安全与密码学2024arxiv.org
智能电视中的自动内容识别（ACR）追踪
Automatic Content Recognition Tracking in Smart TVs
进阶 · 约 35 分钟读完前置知识：网络流量分析、隐私测量基础、广告技术基础
导读
这篇论文研究智能电视中的自动内容识别（ACR）追踪：电视会截取屏幕画面生成内容指纹并上传，用于投放定向广告。论文梳理了该技术的工作机制、数据采集与共享方式及其隐私影响，并给出测量或分析结果。评论指出，这类功能常被包装成“个性化”选项，用户难以察觉自己已经默认开启。
HN 关注点：隐私被常态化侵犯，以及广告技术带来的实际成本；讨论焦点集中在如何识别并关闭 ACR，以及这一行业是否带来任何社会价值。
HN 评论精选
这几条评论里：支持 1 补充 2
补充广告既是隐私灾难，也是推高所有商品价格的隐性成本。
提醒一下：广告业的存在相当于一种税，推高了你购买一切东西的成本，因为花在广告上的每一美元都没有真正改进产品，最终还得靠涨价来收回。所以除了彻底摧毁个人隐私、把全景监控变成常态之外，它还让你在物质上更穷。不过嘛，至少广告变得“更相关”了——大概、差不多、有时候吧！
kibwen查看英文原文
A reminder that the existence of the advertising industry is a tax that drives up the cost of everything that you buy, because every dollar spent on advertising is a dollar that does not actually improve the product in any way, and yet must be recouped by increasing the price of the product. So in addition to the complete destruction of personal privacy and the normalization of the panopticon, it's also making you materially poorer. But hey, at least ads are more relevant, sorta, almost, sometimes!
支持ACR 追踪耗费大量工程资源却没有社会价值。
这么多工程投入白白浪费，对社会毫无益处。
bschwindHN查看英文原文
So much engineering effort wasted with zero benefit to society.
补充实用建议：ACR 常伪装成“个性化”选项，需按厂商命名逐项关闭并重置设备标识。
除了干脆不买这类设备，或者让它断网之外，如果你已经有这类设备并想退出 ACR（自动内容识别），就要确认自己在设置时没有勾选“个性化”之类的功能。厂商在向用户展示 ACR 选择时，并没有清楚说明勾选意味着什么、设备上的数据会被如何使用，通常只是把它包装成开启“个性化”（一般就是为广告服务）。各家电视或电视相关设备厂商对“ACR”的叫法不同，你得先弄清自家厂商怎么称呼它，才能关掉。Consumer Reports 有一份覆盖多个品牌的指南，讲怎么关闭 ACR：https://www.consumerreports.org/electronics/privacy/how-to-turn-off-smart-tv-snooping-features-a4840102036/ 。如果你发现设备已经是开启状态，可以先取消该选项，在部分司法辖区还可以申请删除设备信息；你也可以在做彻底恢复出厂设置、重新配置之前，先重置设备的标识符（如“PSID”等）。如果完全重置设备，要留意厂商在设置流程中诱导你选择开启的各种手段——很多人都是在不知情的情况下把 ACR 打开的。再补充几份退出指南：https://www.tomsguide.com/how-to/st…
moandcompany查看英文原文
Aside from not having one of these devices at all, or disconnecting it from internet access, if you have one and want to opt-out of ACR (Automatic Content Recognition), you need to make sure that you did not select to 'opt-in' to "personalization" type features on the device. ACR opt-ins are not presented to end-users with a clear statement of what the opt-in means or what will happen with your data from your device and are often presented as turning on "personalization" (generally, for advertising purposes). The various TV or tv-related device manufacturers use different names for "ACR," so you'll need to decipher what your manufacturer calls this to disable the feature. Consumer Reports has a useful guide covering multiple brands on how to turn off ACR: https://www.consumerreports.org/electronics/privacy/how-to-turn-off-smart-tv-snooping-features-a4840102036/ If you find that your device has already been opted-in, you can disable the selection, and submit a request to have your device's information removed in some jurisdictions. You can also select to have your device's identifier id (e.g. "PSID" etc) reset from the device before performing a full factory/configuration reset of the device and setting it up again. If you fully reset the device, you'll want to watch out for the ways the manufacturer will try to get you to opt-in during the setup process. Many people have ACR-turned on without knowing. Adding a few more opt-out guides: https://www.tomsguide.com/how-to/stop-your-snooping-smart-tv-how-to-turn-off-data-collection-for-every-brand https://www.zdnet.com/home-and-office/how-to-disable-acr-and-greatly-reduce-ads-on-every-tv-model-and-why-you-should/ It's also worth firewalling, or at least using dns-based blocking, any "smart tv" type devices on your network. Some of them even do periodic scans of your network and send that information to the manufacturer when they "phone home."
历次讨论
- 2024Hacker News 讨论帖159 分 · 155 评
同领域还值得读
如何入侵一台已关机的电脑：在 Intel ME 中运行未签名代码
How to hack a turned-off computer, or running unsigned code in Intel ME
这篇 Black Hat 2017 白皮书讨论 Intel Management Engine（ME）的安全问题：如何在 ME 中运行未签名代码，以及攻破处于关机状态的电脑的相关…
安全与密码学2017 · 543 分 · 107 评专业 · 约 40 分钟编辑精选比特币：一种点对点的电子现金系统（2008）
Bitcoin: A Peer-to-Peer Electronic Cash System (2008)
中本聪 2008 年发表的比特币白皮书，提出了无需可信第三方的点对点电子现金系统。
安全与密码学2017 · 536 分 · 394 评入门 · 约 45 分钟编辑精选GPRS 加密算法 GEA-1 的密码分析表明存在故意弱点
Cryptanalysis of GPRS Encryption Algorithms GEA-1 suggest intentional weakness
首次公开了对 GPRS 加密算法 GEA-1 和 GEA-2 的密码分析攻击。
安全与密码学2021 · 487 分 · 107 评专业 · 约 90 分钟编辑精选Signal 消息协议的形式化安全分析
A Formal Security Analysis of the Signal Messaging Protocol
用形式化方法分析 Signal 消息协议（TextSecure）的安全性：作者在多阶段密钥交换模型下，借助自动化证明工具对协议的密钥协商与 Double Ratchet 密钥更新…
安全与密码学2016 · 353 分 · 230 评专业 · 约 120 分钟编辑精选A2：模拟恶意硬件
A2: Analog Malicious Hardware
论文研究如何在芯片设计阶段植入模拟电路形式的恶意硬件后门，使其难以被常规检测发现。
安全与密码学2016 · 315 分 · 94 评专业 · 约 75 分钟编辑精选