5.5

CVE-2026-24116: bytecodealliance wasmtime Out-of-bounds Read

CVSS: 5.5v3.1MediumAnalyzed
AliasesUBUNTU-CVE-2026-24116DEBIAN-CVE-2026-24116CGA-46gq-5hc5-36g5
Published 27-01-2026Last modified 27-01-2026
Open JSON

Vulnerability summary

CVE-2026-24116 is a medium (CVSS 5.5) Out-of-bounds Read vulnerability in bytecodealliance wasmtime. EPSS estimates a 0.25% chance of exploitation in the next 30 days, higher than 15.2% of scored vulnerabilities.

Overall risk
22/100
0100
Low · default modelHow is this calculated?
CVSS score
5.5/10
010
Medium · v3.1 (NVD)
EPSS score
0.25%
0%100%
Low · +0.02 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 0 · Related 1
CGA-RH6H-3QQX-5HV9

Timeline

  1. 27-01-2026
    PublishedVulnerability first disclosed.
  2. 27-01-2026
    Last modifiedVulnerability information updated.

Description

Wasmtime is a runtime for WebAssembly. Starting in version 29.0.0 and prior to version 36.0.5, 40.0.3, and 41.0.1, on x86-64 platforms with AVX, Wasmtime's compilation of the `f64.copysign` WebAssembly instruction with Cranelift may load 8 more bytes than is necessary. When signals-based-traps are disabled this can result in a uncaught segfault due to loading from unmapped guard pages. With guard pages disabled it's possible for out-of-sandbox data to be loaded, but unless there is another bug in Cranelift this data is not visible to WebAssembly guests. Wasmtime 36.0.5, 40.0.3, and 41.0.1 have been released to fix this issue. Users are recommended to upgrade to the patched versions of Wasmtime. Other affected versions are not patched and users should updated to supported major version instead. This bug can be worked around by enabling signals-based-traps. While disabling guard pages can be a quick fix in some situations, it's not recommended to disabled guard pages as it is a key defense-in-depth measure of Wasmtime.

CVSS metrics

9 scores · 7 sources · 2 versions

EPSS trend

Probability

0.25%

Chance of exploitation in the next 30 days

Percentile

15%

Versus all other CVEs

30-day change

+0.02 pp

From 0.23% on 20-09-2026

20-09-202620-10-2026
EPSS score
0.25%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Chainguard5 products
  • wasmcloud< 2.0.1-r0
  • wizer< 10.0.0-r4
  • yara-x< 1.12.0-r1
  • zed< 0.228.0-r3
  • zellij< 0.44.0-r0
Wolfi5 products
  • wasmcloud< 2.0.1-r0
  • wizer< 10.0.0-r4
  • yara-x< 1.12.0-r1
  • zed< 0.228.0-r3
  • zellij< 0.44.0-r0
Bytecodealliance1 product
  • wasmtime≥ 37.0.0, < 40.0.3 | = 41.0.0 | ≥ 29.0.0, < 36.0.5 | ≥ 40.0.0, < 40.0.3 | ≥ 41.0.0, < 41.0.1
Crates.Io1 product
  • wasmtime≥ 29.0.0, < 36.0.5 | ≥ 37.0.0, < 40.0.3 | ≥ 41.0.0, < 41.0.1
Debian1 product
  • rust-wasmtime< 36.0.5+dfsg-1
Ubuntu1 product
  • rust-wasmtimeAll versions (No fix recorded)

6 vendors · 14 products

References

15 links
Show all 15 references