CVE-2026-115381 json
Wasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 Unbounded Host Memory Allocation via SinkOutputStream write-zeroes
published 2026-10-02 38 d ago modified 2026-10-26 13 d ago also EUVD-2026-108306 , GHSA-gqmc-89g8-p25r , RUSTSEC-2026-0322
- cvss
- 4.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 11%
- public exploits
- 0
- none known
Summary
Wasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 contains an unbounded memory allocation in the wasmtime-wasi WASIp2 write-zeroes method of SinkOutputStream, the default stream used when stdout/stderr are not configured. A malicious WebAssembly guest can request huge zero-filled writes, exhausting host memory and causing denial of service.
Patch / fix
- crates.io wasmtime-wasi 36.0.17, 48.0.4, 49.0.2
- bytecodealliance wasmtime 36.0.17, 48.0.4, 49.0.2
- rust-wasmtime Debian 14 36.0.20+dfsg-1
debian advisories DEBIAN-CVE-2026-115381
- github.com/bytecodealliance/wasmtime#14482 pull request
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 13 d ago
Exploit prediction
0.21% chance of exploitation in the next 30 days, higher than 11% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 5.9 | 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 |
| CNA | 3.1 | 4.8 | CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:H |
| CNA | 4.0 | 5.9 | 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 |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| crates.io | wasmtime-wasi | >=0.0.0-0, <36.0.17 >=37.0.0, <48.0.4 >=49.0.0, <49.0.2 |
36.0.17 48.0.4 49.0.2 |
Affected products
- bytecodealliance wasmtime
Classification
- Weakness
-
- CWE-770 Allocation of Resources Without Limits or Throttling
References
-
github.com
/bytecodealliance/wasmtime/pull/14482
web
-
github.com
/bytecodealliance/wasmtime/security/advisories/GHSA-gqmc-89g8-p25r
vendor-advisory
-
vulncheck.com
/advisories/wasmtime-before-36.0.17-37.0.0-before-48.0.4-and-49.0.0-before-49.0.2-unbounded-host-memory-alloca
third-party-advisory
-
crates.io
/crates/wasmtime-wasi
package
-
rustsec.org
/advisories/RUSTSEC-2026-0322.html
advisory
Sources
- CVE List CVE-2026-115381
- NVD CVE-2026-115381
- OSV RUSTSEC-2026-0322
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.