HTTP/2 Rapid reset attack The HTTP/2 protocol allows clients to indicate to the server that a previous stream should be canceled by sending a RSTSTREAM frame. The protocol does not require the client and server to coordinate the cancellation in any way, the client may do it unilaterally. The client may also assume that the cancellation will take effect immediately when the server receives the RSTSTREAM frame, before any other data from that TCP connection is processed.

Abuse of this feature is called a Rapid Reset attack because it relies on the ability for an endpoint to send a RSTSTREAM frame immediately after sending a request frame, which makes the other endpoint start working and then rapidly resets the request. The request is canceled, but leaves the HTTP/2 connection open.

The HTTP/2 Rapid Reset attack built on this capability is simple: The client opens a large number of streams at once as in the standard HTTP/2 attack, but rather than waiting for a response to each request stream from the server or proxy, the client cancels each request immediately.

The ability to reset streams immediately allows each connection to have an indefinite number of requests in flight. By explicitly canceling the requests, the attacker never exceeds the limit on the number of concurrent open streams. The number of in-flight requests is no longer dependent on the round-trip time (RTT), but only on the available network bandwidth.

In a typical HTTP/2 server implementation, the server will still have to do significant amounts of work for canceled requests, such as allocating new stream data structures, parsing the query and doing header decompression, and mapping the URL to a resource. For reverse proxy implementations, the request may be proxied to the backend server before the RSTSTREAM frame is processed. The client on the other hand paid almost no costs for sending the requests. This creates an exploitable cost asymmetry between the server and the client.

Multiple software artifacts implementing HTTP/2 are affected. This advisory was originally ingested from the swift-nio-http2 repo advisory and their original conent follows.

swift-nio-http2 specific advisory swift-nio-http2 is vulnerable to a denial-of-service vulnerability in which a malicious client can create and then reset a large number of HTTP/2 streams in a short period of time. This causes swift-nio-http2 to commit to a large amount of expensive work which it then throws away, including creating entirely new Channels to serve the traffic. This can easily overwhelm an EventLoop and prevent it from making forward progress.

swift-nio-http2 1.28 contains a remediation for this issue that applies reset counter using a sliding window. This constrains the number of stream resets that may occur in a given window of time. Clients violating this limit will have their connections torn down. This allows clients to continue to cancel streams for legitimate reasons, while constraining malicious actors.

An issue in Tamakihamanoki Line v.13.6.1 allows attackers to send crafted notifications via leakage of the channel access token.

An issue in craftbeer bar canvas mini-app on Line v13.6.1 allows attackers to send crafted malicious notifications via leakage of the channel access token (via captured network traffic).

LINE client for iOS versions prior to 26.3.0 contains a vulnerability in the in-app browser where opening a crafted web page can repeatedly trigger OS-level dialogs due to insufficient safeguards when handling arbitrary URL schemes, potentially causing the iOS device to become temporarily inoperable.

The in-app browser of LINE client for iOS versions below 14.9.0 contains a Universal XSS (UXSS) vulnerability. This vulnerability allows for cross-site scripting (XSS) where arbitrary JavaScript can be executed in the top frame from an embedded iframe on any displayed web site within the in-app browser. The in-app browser is usually opened by tapping on URLs contained in chat messages, and for the attack to be successful, the victim must trigger a click event on a malicious iframe. If an iframe embedded in any website can be controlled by an attacker, this vulnerability could be exploited to capture or alter content displayed in the top frame, as well as user session information. This vulnerability affects LINE client for iOS versions below 14.9.0 and does not affect other LINE clients such as LINE client for Android. Please update LINE client for iOS to version 14.9.0 or higher.

Impact

The SAML implementation provided by armeria-saml currently accepts unsigned SAML messages (assertions, logout requests, etc.) as they are, rather than rejecting them by default. As a result, an attacker can forge a SAML message to authenticate themselves, despite the fact that such an unsigned SAML message should be rejected.

Patches

The vulnerability has been patched in Armeria version 1.27.2. All users who rely on armeria-saml older than version 1.27.2 must upgrade to 1.27.2 or later.

Workarounds

There is no known workaround for this vulnerability.

References

SamlMessageUtil.validateSignature()

Vulnerability Overview A vulnerability has been identified in Central Dogma versions prior to 0.64.1, allowing for the leakage of user sessions and subsequent authentication bypass. The issue stems from a Cross-Site Scripting (XSS) attack vector that targets the RelayState of Security Assertion Markup Language (SAML).

Impact Successful exploitation of this vulnerability enables malicious actors to leak user sessions, leading to the compromise of authentication mechanisms. This, in turn, can facilitate unauthorized access to sensitive resources.

Patches This vulnerability is addressed and resolved in Central Dogma version 0.64.1 Users are strongly encouraged to upgrade to this version or later to mitigate the risk associated with the authentication bypass.

Workarounds No viable workarounds are currently available for this vulnerability. It is recommended to apply the provided patch promptly.

References - OASIS SAML v2.0 Errata 05 - OWASP XSS Prevention Cheat Sheet

LINE client for iOS before 11.15.0 might expose authentication information for a certain service to external entities under certain conditions. This is usually impossible, but in combination with a server-side bug, attackers could get this information.

Central Dogma allows privilege escalation with mirroring to the internal dogma repository that has a file managing the authorization of the project.

LINE client for iOS before 10.16.3 allows cross site script with specific header in WebView.

LINE client for iOS prior to 15.4 allows man-in-the-middle attacks due to improper SSL/TLS certificate validation in an integrated financial SDK. The SDK interfered with the application's network processing, causing server certificate verification to be disabled for a significant portion of network traffic, which could allow a network-adjacent attacker to intercept or modify encrypted communications.

LINE client for iOS prior to 15.19 allows UI spoofing due to inconsistencies between the navigation state and the in-app browser's user interface, which could create confusion about the trust context of displayed pages or interactive elements under specific conditions.

Impact Successful exploitation of this vulnerability could allow an attacker to craft a malicious link that, when clicked by a victim, redirects them to a phishing website designed to mimic the legitimate Central Dogma login page. This could result in the compromise of user accounts and unauthorized access to the Central Dogma instance.

Patches This vulnerability is addressed and resolved in Central Dogma version 0.78.0. The server operators who run Central Dogma server with Shiro authentication are strongly encouraged to upgrade to this version or later to mitigate the risk associated with the open redirect vulnerability.

Workarounds Implement AuthProvider to overrides webLoginService().

References - https://cwe.mitre.org/data/definitions/601.html

LINE client for Android versions from 13.8 to 15.5 is vulnerable to UI spoofing in the in-app browser where a specific layout could obscure the full-screen warning prompt, potentially allowing attackers to conduct phishing attacks.

LINE client for Android versions prior to 14.20 contains a UI spoofing vulnerability in the in-app browser where the full-screen security Toast notification is not properly re-displayed when users return from another application, potentially allowing attackers to conduct phishing attacks by impersonating legitimate interfaces.

The in-app browser in LINE client for iOS versions prior to 14.14 is vulnerable to address bar spoofing, which could allow attackers to execute malicious JavaScript within iframes while displaying trusted URLs, enabling phishing attacks through overlaid malicious content.

Lack of TLS certificate verification in log transmission of a financial module within LINE client for iOS prior to 13.16.0.

An issue in Yoruichi hobby base mini-app on Line v13.6.1 allows attackers to send crafted malicious notifications via leakage of the channel access token.

An issue in Q co ltd mini-app on Line v13.6.1 allows attackers to send crafted malicious notifications via leakage of the channel access token.

An issue in picot.golf mini-app on Line v13.6.1 allows attackers to send crafted malicious notifications via leakage of the channel access token.

An issue in kosei entertainment esportsstudioLegends mini-app on Line v13.6.1 allows attackers to send crafted malicious notifications via leakage of the channel access token.

An issue in kimono-oldnew mini-app on Line v13.6.1 allows attackers to send crafted malicious notifications via leakage of the channel access token.

An issue in STOCKMAN GROUP mini-app on Line v13.6.1 allows attackers to send crafted malicious notifications via leakage of the channel access token.

An issue in mimasakafarm mini-app on Line v13.6.1 allows attackers to send crafted malicious notifications via leakage of the channel access token.

An issue in CHIGASAKI BAKERY mini-app on Line v13.6.1 allows attackers to send crafted malicious notifications via leakage of the channel access token.

An issue in Cleaningmakotoya mini-app on Line v13.6.1 allows attackers to send crafted malicious notifications via leakage of the channel access token.

An issue in angel coffee mini-app on Line v13.6.1 allows attackers to send crafted malicious notifications via leakage of the channel access token.

An issue in mokumoku chohu mini-app on Line v13.6.1 allows attackers to send crafted malicious notifications via leakage of the channel access token.

An issue in A-WORLD OIRASE BEERwaiting Line v.13.6.1 allows attackers to send crafted notifications via leakage of the channel access token.

An issue in Otakara lapis totuka mini-app on Line v13.6.1 allows attackers to send crafted malicious notifications via leakage of the channel access token.