CVE-2026-115390

Wasmtime 47.0.0 before 48.0.3 and 49.0.0 before 49.0.1 Fuel Accounting Bypass DoS

6.9 MediumFix available

Wasmtime 47.0.0 before 48.0.3 and 49.0.0 before 49.0.1 contains a fuel accounting flaw in Cranelift-compiled call_ref and try_table catch paths. Malicious guests can reset consumed fuel after calls to run exponentially long on linear fuel, evading timeouts and periodic yields for denial of service.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: Low
User interaction: Passive

What an attacker can affect

Confidentiality: None
Integrity: None
Availability: High

Exploit likelihood

0.24%Up 0.1 points since Oct 23, 2026

What each source reports

CVE List Score used 6.9

Wasmtime 47.0.0 before 48.0.3 and 49.0.0 before 49.0.1 Fuel Accounting Bypass DoS

Record: CVE-2026-115390
CVSS 4.0: 6.9 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CVSS 3.1: 5.7 MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H
Weakness: CWE-400
Updated: 2026-11-02

EUVDEUVD-2026-108321 6.9

Record: EUVD-2026-108321
CVSS 4.0: 6.9 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Updated: 2026-11-02

GitHub AdvisoriesGHSA-78f8-6g96-699x 6.9

Wasmtime 47.0.0 before 48.0.3 and 49.0.0 before 49.0.1 contains a fuel accounting flaw in...

Record: GHSA-78f8-6g96-699x
CVSS 4.0: 6.9 MediumCVSS: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
CVSS 3.1: 5.7 MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H
Weakness: CWE-400
Updated: 2026-11-02

NVD 6.9

Record: CVE-2026-115390
CVSS 4.0: 6.9 MediumCVSS: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
CVSS 3.1: 5.7 MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H
Weakness: CWE-400
Updated: 2026-11-02

OSV 6.9

Wasmtime 47.0.0 before 48.0.3 and 49.0.0 before 49.0.1 Fuel Accounting Bypass DoS

Record: CVE-2026-115390
CVSS 4.0: 6.9 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Weakness: CWE-400
Updated: 2026-11-02

OSVRUSTSEC-2026-0315 5.7

`call_ref` and exception `catch` can drop some fuel accounting, leading to exponential fuel amplification

This is an entry in the RustSec database for the Wasmtime security advisory located at https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-m63x-6p34-q65x For more information see the GitHub-hosted security advisory.

Record: RUSTSEC-2026-0315
CVSS 3.1: 5.7 MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H
Updated: 2026-11-02

OSVUBUNTU-CVE-2026-115390 6.9

Record: UBUNTU-CVE-2026-115390
CVSS 4.0: 6.9 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CVSS 3.1: 5.7 MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H
Updated: 2026-11-02

Affected products

bytecodealliance wasmtime

Affected packages

Affected packages
Package	Affected	Fixed
`wasmtime` crates.io	47.0.0 up to 48.0.3, 49.0.0 up to 49.0.1	48.0.349.0.1
`rust-wasmtime` Ubuntu:24.04:LTS	All versions, plus listed versions 10.0.1+dfsg-715.0.1+dfsg-416.0.0+dfsg-216.0.0+dfsg-3	None known
`rust-wasmtime` Ubuntu:26.10	All versions, plus listed versions 36.0.5+dfsg-136.0.13+dfsg-1	None known
`rust-wasmtime` Ubuntu:26.04:LTS	All versions, plus listed versions 26.0.1+dfsg-326.0.1+dfsg-428.0.1+dfsg-329.0.1+dfsg-536.0.5+dfsg-1	None known

History

History
Recorded	Changed	Sources
Nov 2, 2026	first indexed	CVE List, EUVD, GitHub Advisories, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2026-115390 is a medium vulnerability (CVSS 6.9) in Bytecodealliance Wasmtime, published September 24, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.24%, the 15th percentile. Fixed in wasmtime 48.0.3.

References

Show 4 moreShow less