Reliance on Undefined Affecting ecs-service-connect-agent package, versions <0:v1.27.0.0-1.amzn2023


Severity

Recommended
0.0
high
0
10

Based on Amazon Linux security rating.

Threat Intelligence

EPSS
0.15% (53rd percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk IDSNYK-AMZN2023-ECSSERVICECONNECTAGENT-5912291
  • published21 Sept 2023
  • disclosed27 Apr 2023

Introduced: 27 Apr 2023

CVE-2023-30624  (opens in a new tab)
CWE-758  (opens in a new tab)

How to fix?

Upgrade Amazon-Linux:2023 ecs-service-connect-agent to version 0:v1.27.0.0-1.amzn2023 or higher.
This issue was patched in ALAS2023-2023-344.

NVD Description

Note: Versions mentioned in the description apply only to the upstream ecs-service-connect-agent package and not the ecs-service-connect-agent package as distributed by Amazon-Linux. See How to fix? for Amazon-Linux:2023 relevant fixed versions and status.

Wasmtime is a standalone runtime for WebAssembly. Prior to versions 6.0.2, 7.0.1, and 8.0.1, Wasmtime's implementation of managing per-instance state, such as tables and memories, contains LLVM-level undefined behavior. This undefined behavior was found to cause runtime-level issues when compiled with LLVM 16 which causes some writes, which are critical for correctness, to be optimized away. Vulnerable versions of Wasmtime compiled with Rust 1.70, which is currently in beta, or later are known to have incorrectly compiled functions. Versions of Wasmtime compiled with the current Rust stable release, 1.69, and prior are not known at this time to have any issues, but can theoretically exhibit potential issues.

The underlying problem is that Wasmtime's runtime state for an instance involves a Rust-defined structure called Instance which has a trailing VMContext structure after it. This VMContext structure has a runtime-defined layout that is unique per-module. This representation cannot be expressed with safe code in Rust so unsafe code is required to maintain this state. The code doing this, however, has methods which take &amp;self as an argument but modify data in the VMContext part of the allocation. This means that pointers derived from &amp;self are mutated. This is typically not allowed, except in the presence of UnsafeCell, in Rust. When compiled to LLVM these functions have noalias readonly parameters which means it's UB to write through the pointers.

Wasmtime's internal representation and management of VMContext has been updated to use &amp;mut self methods where appropriate. Additionally verification tools for unsafe code in Rust, such as cargo miri, are planned to be executed on the main branch soon to fix any Rust-level issues that may be exploited in future compiler versions.

Precomplied binaries available for Wasmtime from GitHub releases have been compiled with at most LLVM 15 so are not known to be vulnerable. As mentioned above, however, it's still recommended to update.

Wasmtime version 6.0.2, 7.0.1, and 8.0.1 have been issued which contain the patch necessary to work correctly on LLVM 16 and have no known UB on LLVM 15 and earlier. If Wasmtime is compiled with Rust 1.69 and prior, which use LLVM 15, then there are no known issues. There is a theoretical possibility for undefined behavior to exploited, however, so it's recommended that users upgrade to a patched version of Wasmtime. Users using beta Rust (1.70 at this time) or nightly Rust (1.71 at this time) must update to a patched version to work correctly.

CVSS Scores

version 3.1