Impact

There is an unauthenticated remote code execution vulnerability in React Server Components.

We recommend upgrading immediately.

The vulnerability is present in versions 19.0.0, 19.1.0, 19.1.1, and 19.2.0 of: react-server-dom-webpack react-server-dom-parcel react-server-dom-turbopack

Patches

A fix was introduced in versions 19.0.1, 19.1.2, and 19.2.1. If you are using any of the above packages please upgrade to any of the fixed versions immediately.

If your app’s React code does not use a server, your app is not affected by this vulnerability. If your app does not use a framework, bundler, or bundler plugin that supports React Server Components, your app is not affected by this vulnerability.

References

See the blog post for more information and upgrade instructions.

react-dev-utils on Windows allows developers to run a local webserver for accepting various commands, including a command to launch an editor. The input to that command was not properly sanitized, allowing an attacker who can make a network request to the server (either via CSRF or by direct request) to execute arbitrary commands on the targeted system. This issue affects multiple branches: 1.x.x prior to 1.0.4, 2.x.x prior to 2.0.2, 3.x.x prior to 3.1.2, 4.x.x prior to 4.2.2, and 5.x.x prior to 5.0.2.

A lack of input validation exists in tacplus prior to commit 4fdf178 which, when pre or post auth commands are enabled, allows an attacker who can control the username, rem-addr, or NAC address sent to tacplus to inject shell commands and gain remote code execution on the tacplus server.

A type confusion vulnerability could be triggered when resolving the "typeof" unary operator in Facebook Hermes prior to v0.10.0. Note that this is only exploitable if the application using Hermes permits evaluation of untrusted JavaScript. Hence, most React Native applications are not affected.

Improper handling of closenotify alerts can result in an out-of-bounds read in AsyncSSLSocket. This issue affects folly prior to v2019.11.04.00.

In the course of decompressing HPACK inside the HTTP2 protocol, an unexpected sequence of header table resize operations can place the header table into a corrupted state, leading to a use-after-free condition and undefined behavior. This issue affects Proxygen from v0.29.0 until v2017.04.03.00.

An invalid free in mbdetectorder can cause the application to crash or potentially result in remote code execution. This issue affects HHVM versions prior to 3.30.12, all versions between 4.0.0 and 4.8.5, all versions between 4.9.0 and 4.23.1, as well as 4.24.0, 4.25.0, 4.26.0, 4.27.0, 4.28.0, and 4.28.1.

Insufficient boundary checks when processing a string in mberegreplace allows access to out-of-bounds memory. This issue affects HHVM versions prior to 3.30.12, all versions between 4.0.0 and 4.8.5, all versions between 4.9.0 and 4.23.1, as well as 4.24.0, 4.25.0, 4.26.0, 4.27.0, 4.28.0, and 4.28.1.

Various APC functions accept keys containing null bytes as input, leading to premature truncation of input. This issue affects HHVM versions prior to 3.30.12, all versions between 4.0.0 and 4.8.5, all versions between 4.9.0 and 4.23.1, as well as 4.24.0, 4.25.0, 4.26.0, 4.27.0, 4.28.0, and 4.28.1.

A use after free in hermes, while emitting certain error messages, prior to commit d86e185e485b6330216dee8e854455c694e3a36e allows attackers to potentially execute arbitrary code via crafted JavaScript. Note that this is only exploitable if the application using Hermes permits evaluation of untrusted JavaScript. Hence, most React Native applications are not affected.

xbufformatconverter, used as part of exifreaddata, was appending a terminating null character to the generated string, but was not using its standard append char function. As a result, if the buffer was full, it would result in an out-of-bounds write. This issue affects HHVM versions prior to 4.56.3, all versions between 4.57.0 and 4.80.1, all versions between 4.81.0 and 4.93.1, and versions 4.94.0, 4.95.0, 4.96.0, 4.97.0, 4.98.0.

Facebook react-dev-utils could allow a remote attacker to execute arbitrary commands on the system, caused by a flaw in getProcessForPort function. By sending a specially-crafted request, an attacker could exploit this vulnerability to inject and execute arbitrary commands on the system.

Due to incorrect string size calculations inside the pregquote function, a large input string passed to the function can trigger an integer overflow leading to a heap overflow. This issue affects HHVM versions prior to 4.56.3, all versions between 4.57.0 and 4.80.1, all versions between 4.81.0 and 4.93.1, and versions 4.94.0, 4.95.0, 4.96.0, 4.97.0, 4.98.0.

When unserializing an object with dynamic properties HHVM needs to pre-reserve the full size of the dynamic property array before inserting anything into it. Otherwise the array might resize, invalidating previously stored references. This pre-reservation was not occurring in HHVM prior to v4.32.3, between versions 4.33.0 and 4.56.0, 4.57.0, 4.58.0, 4.58.1, 4.59.0, 4.60.0, 4.61.0, 4.62.0.

An incorrect size calculation in ldapescape may lead to an integer overflow when overly long input is passed in, resulting in an out-of-bounds write. This issue affects HHVM prior to 4.56.2, all versions between 4.57.0 and 4.78.0, 4.79.0, 4.80.0, 4.81.0, 4.82.0, 4.83.0.

A logic vulnerability when handling the SaveGeneratorLong instruction in Facebook Hermes prior to commit b2021df620824627f5a8c96615edbd1eb7fdddfc allows attackers to potentially read out of bounds or theoretically execute arbitrary code via crafted JavaScript. Note that this is only exploitable if the application using Hermes permits evaluation of untrusted JavaScript. Hence, most React Native applications are not affected.

A use-after-free is possible due to an error in lifetime management in the request adaptor when a malicious client invokes request error handling in a specific sequence. This issue affects versions of proxygen prior to v2020.05.18.00.

hhvm before 3.12.11 has a use-after-free in the serializememoizeparam() and ResourceBundle::construct() functions.

An out of bounds write is possible via a specially crafted packet in certain configurations of Proxygen due to improper handling of Base64 when parsing malformed binary content in Structured HTTP Headers. This issue affects versions of proxygen prior to v2019.07.22.00.

Integer overflow in StringUtil::implode in Facebook HHVM before 3.15.0 allows attackers to have unspecified impact via unknown vectors.

Self recursion in compact in Facebook HHVM before 3.15.0 allows attackers to have unspecified impact via unknown vectors.

Infinite recursion in wddx in Facebook HHVM before 3.15.0 allows attackers to have unspecified impact via unknown vectors.

The arrayrecursive functions in Facebook HHVM before 3.15.0 allows attackers to have unspecified impact via unknown vectors, related to recursion.

Out-of-bounds write in the (1) mbdetectencoding, (2) mbsendmail, and (3) mbdetectorder functions in Facebook HHVM before 3.15.0 allows attackers to have unspecified impact via unknown vectors.

Integer overflow in bcmath in Facebook HHVM before 3.15.0 allows attackers to have unspecified impact via unknown vectors, which triggers a buffer overflow.

By passing invalid javascript code where await and yield were called upon non-async and non-generator getter/setter functions, Hermes would invoke generator functions and error out on invalid await/yield positions. This could result in segmentation fault as a consequence of type confusion error, with a low chance of RCE. This issue affects Hermes versions prior to v0.10.0.

Due to use of unsafe YAML deserialization logic, an attacker with the ability to modify local YAML configuration files could provide malicious input, resulting in remote code execution or similar risks. This issue affects ParlAI prior to v1.1.0.

Passing an attacker controlled size when creating an IOBuf could cause integer overflow, leading to an out of bounds write on the heap with the possibility of remote code execution. This issue affects versions of folly prior to v2021.07.22.00. This issue affects HHVM versions prior to 4.80.5, all versions between 4.81.0 and 4.102.1, all versions between 4.103.0 and 4.113.0, and versions 4.114.0, 4.115.0, 4.116.0, 4.117.0, 4.118.0 and 4.118.1.

An invalid free in Thrift's table-based serialization can cause the application to crash or potentially result in code execution or other undesirable effects. This issue affects Facebook Thrift prior to v2021.02.22.00.

The fbgames protocol handler registered as part of Facebook Gameroom does not properly quote arguments passed to the executable. That allows a malicious URL to cause code execution. This issue affects versions prior to v1.26.0.