Vulnerability feed

Executive summary

The advisory is a diff of a Wasmtime source file, a WebAssembly runtime, changing how internal value data is packed in the Cranelift code generator. The text does not describe a security impact, severity rating, or recommended action from the vendor, and it does not name affected or fixed versions.

Technical summary

The diff changes the ValueDataPacked layout in cranelift/codegen/src/ir/dfg.rs from a packed u64 with 24-bit x and y fields to a repr(Rust, packed) struct with 32-bit x and y fields and a 16-bit flags_and_type field, and removes the encode_narrow_field and decode_narrow_field helpers. The advisory text does not state a vulnerability class, attack vector, or preconditions, and it does not state affected versions, fixed versions, workarounds, exploitation status, or a CVSS score. No detection guidance is given. The text is a code diff only, so the security impact is not stated.

Summaries are generated by AI from the linked advisory text. Confirm versions and fixes at the source.

Summarized from github.com/bytecodealliance/wasmtime/co…fa75cd9d03f4a438dae0

Impact if exploited

How it is exploited

Attack vector

Network

Attack complexity

Low

Privileges required

Low

User interaction

None

Scope

Changed

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Affects

bytecodeallianceWasmtimebytecodealliance wasmtimeWasmtime

Executive summary

A flaw in Wasmtime, a WebAssembly runtime library, lets an embedder mix objects from two different engines, which can cause memory corruption. The advisory rates it Low severity with a CVSS overall score of 3.8, and it is not triggerable by guest WebAssembly programs or the wasmtime CLI. The vendor strongly recommends upgrading the wasmtime crate to a patched version, and embedders using a single engine are not affected.

Technical summary

The issue is a type confusion weakness (CWE-843) that also enables a potential out-of-bounds write (CWE-787), where a trampoline compiled for one signature may write return values past a stack allocation. Exploitation requires an embedder that creates two Engine instances and mixes Module, Component, type, or Tag objects between them; the advisory states that guest WebAssembly cannot trigger it. Affected ranges are at or below 24.0.11, 25.0.0 through 36.0.12, 37.0.0 through 46.0.1, and 47.0.0 through 47.0.2, with patched versions 24.0.12, 36.0.13, 46.0.2, and 47.0.3. The advisory gives a workaround of checking Engine::same(store.engine(), module.engine()) before instantiation, but it does not state any detection guidance or whether exploitation has occurred in the wild.

Summaries are generated by AI from the linked advisory text. Confirm versions and fixes at the source.

Summarized from github.com/bytecodealliance/wasmtime/se…/GHSA-hgjw-h833-99q9

Impact if exploited

How it is exploited

Attack vector

Local

Attack complexity

High

Attack requirements

Present

Privileges required

High

User interaction

Passive

CVSS:4.0/AV:L/AC:H/AT:P/PR:H/UI:P/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affects

bytecodeallianceWasmtimebytecodealliance wasmtimeWasmtime

Executive summary

A flaw in Wasmtime, a WebAssembly runtime, lets guest code escape its filesystem sandbox and read or write files outside it on the host. The advisory rates it High with a CVSS v4 base score of 8.8 and recommends upgrading to a patched Wasmtime release (24.0.13, 36.0.14, 46.0.3, or 47.0.4, depending on the branch).

Technical summary

The weakness is CWE-61 (UNIX symbolic link following) in the wasmtime-wasi crate, which relies on the cap-std crate, where a trailing slash in paths or symlinks can escape the sandbox. The attack vector is network, with low complexity, requires low privileges, and needs passive user interaction; the advisory's CVSS v4 vector is CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L. Affected versions are listed as up to and including 24.0.12, 25.0.0 through 36.0.13, 37.0.0 through 46.0.2, and 47.0.0 through 47.0.3; patched versions are 24.0.13, 36.0.14, 46.0.3, and 47.0.4, and release 48.0.0 and later is stated as not affected. The advisory says Linux kernels after 5.6 with openat2 are not affected, while macOS and older Linux kernels are. No workaround is stated (the advisory says there is no known workaround), and no detection guidance or evidence of exploitation in the wild is stated.

Summaries are generated by AI from the linked advisory text. Confirm versions and fixes at the source.

Dropped extracted product not named in the source: Bytecode Alliance cap-std

Summarized from github.com/bytecodealliance/wasmtime/se…/GHSA-vqjp-4c8c-hfgg

Impact if exploited

How it is exploited

Attack vector

Network

Attack complexity

Low

Attack requirements

Present

Privileges required

Low

User interaction

Passive

CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affects

bytecodeallianceWasmtimebytecodealliance wasmtimeWasmtimewasmtime-wasi

Executive summary

A flaw in Wasmtime, a WebAssembly runtime, lets a guest program consume fuel-limited execution time in a way that can cause denial of service. The advisory rates it Moderate, with a CVSS 3.1 base score of 5.7 as stated. The vendor recommends upgrading to Wasmtime 48.0.3 or 49.0.1, and says that epoch interruption can be used instead by embedders who only need periodic interruption.

Technical summary

The flaw is a fuel accounting error in code compiled by the Cranelift backend, affecting call_ref callsites and the exceptional catch path for calls within try_table blocks. Fuel consumed in the callee can be dropped and reset to the amount remaining before the call, which can lead to exponential fuel amplification and denial of service. The bug requires fuel to be enabled (Config::consume_fuel or -W fuel=N), which is off by default, and only affects guests containing call_ref or try_table opcodes. Affected versions are stated as >= 47.0.0, < 48.0.3 and 49.0.0, with patched versions 48.0.3 and 49.0.1. The advisory gives epoch interruption as a workaround for embedders who do not need deterministic fuel metering, and says no other workaround exists for them. No detection guidance beyond scanning guest bytecode for the opcodes is stated, and no CWE is listed. Whether exploitation in the wild has occurred is not stated.

Summaries are generated by AI from the linked advisory text. Confirm versions and fixes at the source.

Dropped extracted product not named in the source: Bytecode Alliance wasmtime

Summarized from github.com/bytecodealliance/wasmtime/se…/GHSA-m63x-6p34-q65x

Impact if exploited

How it is exploited

Attack vector

Network

Attack complexity

Low

Attack requirements

None

Privileges required

Low

User interaction

Passive

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affects

bytecodeallianceWasmtimebytecodealliance wasmtimeWasmtime

Executive summary

A flaw in the wasmtime-wasi-http component of the Wasmtime WebAssembly runtime lets guest code exhaust host memory and cause a denial of service. The advisory rates it Moderate with a CVSS v3.1 base score of 6.2 and recommends upgrading to patched versions 36.0.16, 48.0.3, or 49.0.1.

Technical summary

The vulnerability is classified as uncontrolled resource consumption (CWE-400) and allocation without limits (CWE-770). The wasmtime-wasi-http component does not enforce the write allowance returned by wasi:io/streams check-write for WASIp2 outgoing HTTP bodies, so a guest can pass a buffer larger than permitted and have the write succeed, holding host allocations for the lifetime of the store. The advisory states affected versions as before 36.0.16, 37.0.0 before 48.0.3, and 49.0.0 before 49.0.1, with fixes in 36.0.16, 48.0.3, and 49.0.1. The attack vector is local, requires no privileges or user interaction, and the CVSS vector is CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. No workaround is stated, and no detection guidance is stated. Whether the flaw is exploited in the wild is not stated.

Summaries are generated by AI from the linked advisory text. Confirm versions and fixes at the source.

Summarized from github.com/bytecodealliance/wasmtime/se…/GHSA-c9gc-w9vx-w86p

Impact if exploited

How it is exploited

Attack vector

Local

Attack complexity

Low

Attack requirements

None

Privileges required

None

User interaction

None

CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affects

bytecodeallianceWasmtimebytecodealliance wasmtimewasmtime-wasi-http

Executive summary

Wasmtime, a WebAssembly runtime, has an information disclosure flaw that can leak a few bytes of host memory to guest programs that have a preopened directory. The advisory rates it Low severity, and the vendor recommends upgrading to a patched release because no workaround is available when WASIp1 is enabled with a preopened directory.

Technical summary

The flaw is classified as CWE-908, use of uninitialized resource, in the WASIp1 fd_readdir implementation, where struct padding bytes from the host are copied into guest memory, leaking 3 bytes per directory entry. The attack vector is network with low privileges and passive user interaction, and it only affects guests with a preopened directory when WASIp1 is enabled. Affected versions are stated as before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2, with fixed versions 36.0.17, 48.0.4, and 49.0.2. The advisory states there is no workaround when WASIp1 is enabled and guests have preopened directory access. The advisory does not state whether exploitation in the wild has occurred, and it gives no specific detection guidance.

Summaries are generated by AI from the linked advisory text. Confirm versions and fixes at the source.

Summarized from github.com/bytecodealliance/wasmtime/se…/GHSA-96f6-r43r-8c24

Impact if exploited

How it is exploited

Attack vector

Network

Attack complexity

Low

Attack requirements

Present

Privileges required

Low

User interaction

Passive

CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affects

bytecodeallianceWasmtimebytecodealliance wasmtimeWasmtimewasmtime-wasi

Executive summary

Wasmtime, a WebAssembly runtime, has a flaw in how it validates certain WebAssembly components that import exception tags, affecting versions 47.0.0 before 48.0.4 and 49.0.0 before 49.0.2. The advisory rates it Moderate with a CVSS score of 5.9 and says it can lead to memory corruption in the runtime's GC heap, which may cause crashes. The vendor recommends updating to patched versions 48.0.4 or 49.0.2, and no workaround is known beyond upgrading or disabling the WebAssembly exceptions proposal.

Technical summary

The flaw is an improper validation issue in which Wasmtime accepts components whose core modules import WebAssembly tags with a subtype of the original tag's type, which the WebAssembly specification does not allow. This lets guest code mis-type an exception payload, which can corrupt the GC heap and may cause panics. The advisory states the bug affects only builds with the WebAssembly exceptions proposal enabled, which is on by default starting in Wasmtime 47.0.0. Affected versions are listed as >= 47.0.0, < 48.0.4 and >= 49.0.0, < 49.0.2, with patched versions 48.0.4 and 49.0.2. The CVSS v4 vector is CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N. The advisory states no known workaround exists, and no detection guidance or evidence of in-the-wild exploitation is stated.

Summaries are generated by AI from the linked advisory text. Confirm versions and fixes at the source.

Summarized from github.com/bytecodealliance/wasmtime/se…/GHSA-cfhf-m2cr-62wj

Impact if exploited

How it is exploited

Attack vector

Network

Attack complexity

Low

Attack requirements

Present

Privileges required

Low

User interaction

Passive

CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affects

bytecodeallianceWasmtimebytecodealliance wasmtimeWasmtime

Executive summary

A memory allocation flaw in Wasmtime, a WebAssembly runtime, affects embeddings that do not configure stdout or stderr streams. Exploitation could exhaust memory on the host, and the advisory rates the issue Moderate with a CVSS v4 base score of 5.9. The vendor recommends upgrading to Wasmtime 36.0.17, 48.0.4, or 49.0.2, or applying a custom OutputStream workaround.

Technical summary

The flaw is CWE-770, allocation of resources without limits, in the wasmtime-wasi WASIp2 write-zeroes method for SinkOutputStream, which allows an unlimited-size allocation of a buffer of zeros on the host. It affects only embeddings that do not configure stdout or stderr streams, and the CVSS v4 vector indicates network attack vector, low attack complexity, low privileges required, passive user interaction, and high availability impact. Affected versions are below 36.0.17, from 37.0.0 before 48.0.4, and from 49.0.0 before 49.0.2, with fixed versions 36.0.17, 48.0.4, and 49.0.2. The advisory recommends a custom OutputStream whose check_write returns a limited value as a workaround, or updating to a patch release. The advisory does not state whether the issue is being exploited in the wild, and it does not provide specific detection guidance.

Summaries are generated by AI from the linked advisory text. Confirm versions and fixes at the source.

Summarized from github.com/bytecodealliance/wasmtime/se…/GHSA-gqmc-89g8-p25r

Impact if exploited

How it is exploited

Attack vector

Network

Attack complexity

Low

Attack requirements

Present

Privileges required

Low

User interaction

Passive

CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affects

bytecodeallianceWasmtimebytecodealliance wasmtimewasmtime-wasi

Executive summary

A flaw in the Wasmtime WebAssembly runtime's WASI preview 0 poll_oneoff adapter lets guest code run long computations that skip fuel limits, enabling denial of service on affected hosts. The advisory rates it Moderate with a CVSS 3.1 base score of 4.0, and the vendor's fix is to upgrade to patched releases (36.0.17, 48.0.4, or 49.0.2) or disable WASI preview 0 in the CLI.

Technical summary

The weakness is a resource exhaustion issue: the WASI preview 0 poll_oneoff adapter in wasmtime-wasi performs work proportional to the number of subscriptions without consuming fuel or checking whether fuel has run out, because the adapter rewrites each subscription before calling the WASI preview 1 implementation, which is the only path with a fuel check. The attack requires a local guest with no privileges, and the CVSS vector is AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L. Affected versions are below 36.0.17, from 37.0.0 before 48.0.4, and from 49.0.0 before 49.0.2; patched versions are 36.0.17, 48.0.4, and 49.0.2. The CLI is affected by default, while library users are affected only if they explicitly enable WASI preview 0. The stated workaround is disabling WASI preview 0 in the CLI with -Spreview0=n. The advisory does not state any detection guidance or evidence of exploitation in the wild.

Summaries are generated by AI from the linked advisory text. Confirm versions and fixes at the source.

Summarized from github.com/bytecodealliance/wasmtime/se…/GHSA-j366-h8gg-77pm

Impact if exploited

How it is exploited

Attack vector

Local

Attack complexity

Low

Attack requirements

None

Privileges required

None

User interaction

None

CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affects

bytecodeallianceWasmtimebytecodealliance wasmtimewasmtime-wasiWasmtime CLI