点按 新增标签，建立新的标签名称与新增成员，或于新增成员中，将朋友加入已设定的标签内。
The servers keep registered end users' cell phone numbers, general public critical substance and thrust tokens which might be needed for creating calls and transmitting messages.[174] In order to pick which contacts are Sign users, cryptographic hashes in the user's contact quantities are periodically transmitted on the server.[175] The server then checks to discover if People match any in the SHA-256 hashes of registered users and tells the shopper if any matches are identified.[175] The hashed quantities are thereafter discarded from your server.[174] In 2014, Moxie Marlinspike wrote that it's very easy to calculate a map of all attainable hash inputs to hash outputs and reverse the mapping because of the constrained preimage House (the set of all attainable hash inputs) of phone figures, Which a "practical privateness preserving Get in touch with discovery stays an unsolved trouble.
[152][153] In July 2017, researchers from RUB identified through A further analysis of group messengers a purely theoretic attack from the team protocol of Sign: A person who knows the secret group ID of a group (on account of acquiring been a gaggle member Beforehand or thieving it from the member's device) can become a member from the group. Because the group ID cannot be guessed and this sort of member alterations are exhibited to the remaining customers, this assault is probably going to get challenging to perform with no staying detected.[154]
TextSecure authorized the consumer to set a passphrase that encrypted the neighborhood message database and the person's encryption keys.[127] This didn't encrypt the consumer's Get in touch with database or information timestamps.[127] The Sign apps on Android and iOS could be locked With all the telephone's pin, passphrase, or biometric authentication.
Signal's app icon can be altered with several different colour themes for personalization and to cover the app. The applying name can even be personalized.[132] Messages might have effects like spoilers and italics, and people can add one another via QR code.[133]
On 9 August 2022, Ismail Sabri Yaakob, the Key Minister of Malaysia, noted that his Sign account was "hacked" and infiltrated by a third party, sending out messages and impersonating the politician. No specifics were being disclosed regarding the system used to obtain usage of the account.[215]
Signal's phrases of assistance states which the products may not be used to violate the law.[237] In accordance with a former personnel, Sign's Management at enough time instructed him they'd say a thing "if and when people today get started abusing Sign or accomplishing things which we expect are awful".
I last but not least received the prospect to go through all this a lot more carefully, and plainly all Cellebrite is performing is looking at the texts off of a cell phone they Signal下载 are able to by now access. To [sic] this has almost nothing to complete with Sign at all. So: never ever mind.
Right up until 2023, Android buyers could opt into building Sign the default SMS/MMS application, letting them to send and obtain unencrypted SMS messages in addition to the normal conclusion-to-end encrypted Signal messages.
This mandatory connection into a phone range (a aspect Signal shares with WhatsApp, KakaoTalk, and Other people) is criticized being a "big difficulty" for privacy-conscious customers who're not cozy with providing out their personal variety.
Among the list of things which I had been briefed on incredibly early, senator, was via the CIA documents administration individuals about using Sign for a permissible get the job done use," Ratcliffe reported. ^
端到端加密：所有消息、语音、文件传输都经过加密，确保第三方无法读取。
On 27 September 2019, Natalie Silvanovich, a protection engineer Functioning in Google's vulnerability study team at Job Zero, disclosed how a bug while in the Android Signal shopper could Permit an attacker spy on a person with no their information.[203] The bug authorized an attacker to cell phone a goal gadget, mute the decision, and the call would complete �?preserving the audio open but with no proprietor being mindful of that (nevertheless they might nevertheless be aware of a ring and / or a vibration with the initial simply call).
Right after obtaining and decrypting messages, the applying stored them regionally on Each individual gadget in the SQLite databases that is encrypted with SQLCipher.[162] The cryptographic crucial for this databases is usually stored locally and may be accessed If your device is unlocked.[162][163] In December 2020, Cellebrite printed a site article asserting that one of their items could now entry this critical and utilize it to "decrypt the Sign application".[162][164] Technologies reporters later revealed articles or blog posts regarding how Cellebrite experienced claimed to obtain a chance to "crack into the Signal application" and "crack Sign's encryption".[a hundred sixty five][166] This latter interpretation was turned down by several experts,[167] in addition to representatives from Signal, who stated the original publish by Cellebrite had been about accessing information on "an unlocked Android telephone within their physical possession" and that they "could have just opened the application to think about the messages".