diff --git a/docs/server-server/security-threat-model.rst b/docs/server-server/security-threat-model.rst deleted file mode 100644 index cf0430e43d..0000000000 --- a/docs/server-server/security-threat-model.rst +++ /dev/null @@ -1,141 +0,0 @@ -Overview -======== - -Scope ------ - -This document considers threats specific to the server to server federation -synapse protocol. - - -Attacker --------- - -It is assumed that the attacker can see and manipulate all network traffic -between any of the servers and may be in control of one or more homeservers -participating in the federation protocol. - -Threat Model -============ - -Denial of Service ------------------ - -The attacker could attempt to prevent delivery of messages to or from the -victim in order to: - - * Disrupt service or marketing campaign of a commercial competitor. - * Censor a discussion or censor a participant in a discussion. - * Perform general vandalism. - -Threat: Resource Exhaustion -~~~~~~~~~~~~~~~~~~~~~~~~~~~ - -An attacker could cause the victims server to exhaust a particular resource -(e.g. open TCP connections, CPU, memory, disk storage) - -Threat: Unrecoverable Consistency Violations -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - -An attacker could send messages which created an unrecoverable "split-brain" -state in the cluster such that the victim's servers could no longer dervive a -consistent view of the chatroom state. - -Threat: Bad History -~~~~~~~~~~~~~~~~~~~ - -An attacker could convince the victim to accept invalid messages which the -victim would then include in their view of the chatroom history. Other servers -in the chatroom would reject the invalid messages and potentially reject the -victims messages as well since they depended on the invalid messages. - -Threat: Block Network Traffic -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - -An attacker could try to firewall traffic between the victim's server and some -or all of the other servers in the chatroom. - -Threat: High Volume of Messages -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - -An attacker could send large volumes of messages to a chatroom with the victim -making the chatroom unusable. - -Threat: Banning users without necessary authorisation -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - -An attacker could attempt to ban a user from a chatroom with the necessary -authorisation. - -Spoofing --------- - -An attacker could try to send a message claiming to be from the victim without -the victim having sent the message in order to: - - * Impersonate the victim while performing illict activity. - * Obtain privileges of the victim. - -Threat: Altering Message Contents -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - -An attacker could try to alter the contents of an existing message from the -victim. - -Threat: Fake Message "origin" Field -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - -An attacker could try to send a new message purporting to be from the victim -with a phony "origin" field. - -Spamming --------- - -The attacker could try to send a high volume of solicicted or unsolicted -messages to the victim in order to: - - * Find victims for scams. - * Market unwanted products. - -Threat: Unsoliticted Messages -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - -An attacker could try to send messages to victims who do not wish to receive -them. - -Threat: Abusive Messages -~~~~~~~~~~~~~~~~~~~~~~~~ - -An attacker could send abusive or threatening messages to the victim - -Spying ------- - -The attacker could try to access message contents or metadata for messages sent -by the victim or to the victim that were not intended to reach the attacker in -order to: - - * Gain sensitive personal or commercial information. - * Impersonate the victim using credentials contained in the messages. - (e.g. password reset messages) - * Discover who the victim was talking to and when. - -Threat: Disclosure during Transmission -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - -An attacker could try to expose the message contents or metadata during -transmission between the servers. - -Threat: Disclosure to Servers Outside Chatroom -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - -An attacker could try to convince servers within a chatroom to send messages to -a server it controls that was not authorised to be within the chatroom. - -Threat: Disclosure to Servers Within Chatroom -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - -An attacker could take control of a server within a chatroom to expose message -contents or metadata for messages in that room. - - diff --git a/docs/specification.rst b/docs/specification.rst index c67b4ca2b4..bae18147a8 100644 --- a/docs/specification.rst +++ b/docs/specification.rst @@ -1625,6 +1625,130 @@ SRV Records Security ======== + +Threat Model +------------ + +Denial of Service +~~~~~~~~~~~~~~~~~ + +The attacker could attempt to prevent delivery of messages to or from the +victim in order to: + + * Disrupt service or marketing campaign of a commercial competitor. + * Censor a discussion or censor a participant in a discussion. + * Perform general vandalism. + +Threat: Resource Exhaustion ++++++++++++++++++++++++++++ + +An attacker could cause the victims server to exhaust a particular resource +(e.g. open TCP connections, CPU, memory, disk storage) + +Threat: Unrecoverable Consistency Violations +++++++++++++++++++++++++++++++++++++++++++++ + +An attacker could send messages which created an unrecoverable "split-brain" +state in the cluster such that the victim's servers could no longer dervive a +consistent view of the chatroom state. + +Threat: Bad History ++++++++++++++++++++ + +An attacker could convince the victim to accept invalid messages which the +victim would then include in their view of the chatroom history. Other servers +in the chatroom would reject the invalid messages and potentially reject the +victims messages as well since they depended on the invalid messages. + +Threat: Block Network Traffic ++++++++++++++++++++++++++++++ + +An attacker could try to firewall traffic between the victim's server and some +or all of the other servers in the chatroom. + +Threat: High Volume of Messages ++++++++++++++++++++++++++++++++ + +An attacker could send large volumes of messages to a chatroom with the victim +making the chatroom unusable. + +Threat: Banning users without necessary authorisation ++++++++++++++++++++++++++++++++++++++++++++++++++++++ + +An attacker could attempt to ban a user from a chatroom with the necessary +authorisation. + +Spoofing +~~~~~~~~ + +An attacker could try to send a message claiming to be from the victim without +the victim having sent the message in order to: + +* Impersonate the victim while performing illict activity. +* Obtain privileges of the victim. + +Threat: Altering Message Contents ++++++++++++++++++++++++++++++++++ + +An attacker could try to alter the contents of an existing message from the +victim. + +Threat: Fake Message "origin" Field ++++++++++++++++++++++++++++++++++++ + +An attacker could try to send a new message purporting to be from the victim +with a phony "origin" field. + +Spamming +~~~~~~~~ + +The attacker could try to send a high volume of solicicted or unsolicted +messages to the victim in order to: + +* Find victims for scams. +* Market unwanted products. + +Threat: Unsoliticted Messages ++++++++++++++++++++++++++++++ + +An attacker could try to send messages to victims who do not wish to receive +them. + +Threat: Abusive Messages +++++++++++++++++++++++++ + +An attacker could send abusive or threatening messages to the victim + +Spying +~~~~~~ + +The attacker could try to access message contents or metadata for messages sent +by the victim or to the victim that were not intended to reach the attacker in +order to: + +* Gain sensitive personal or commercial information. +* Impersonate the victim using credentials contained in the messages. + (e.g. password reset messages) +* Discover who the victim was talking to and when. + +Threat: Disclosure during Transmission +++++++++++++++++++++++++++++++++++++++ + +An attacker could try to expose the message contents or metadata during +transmission between the servers. + +Threat: Disclosure to Servers Outside Chatroom +++++++++++++++++++++++++++++++++++++++++++++++ + +An attacker could try to convince servers within a chatroom to send messages to +a server it controls that was not authorised to be within the chatroom. + +Threat: Disclosure to Servers Within Chatroom +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +An attacker could take control of a server within a chatroom to expose message +contents or metadata for messages in that room. + .. NOTE:: This section is a work in progress.