All vulnerabilities
CVE-2026-115386GHSA-96f6-r43r-8c24

Wasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 Memory Disclosure via fd_readdir

bytecodealliance wasmtime
Open in ThreatlineRecord JSON
CVSS
2.1Low
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.15%Chance of exploitation activity in the next 30 days, higher than 3% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in36.0.17Also 48.0.4, 49.0.2CVE List
Published22 Oct 2026Updated 23 Oct 2026CVE List

What fixes it

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

Description

Wasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 contains an information disclosure vulnerability in the WASIp1 fd_readdir implementation that copies uninitialized struct padding into guest memory. Guests with a preopened directory can list entries to receive three bytes of leftover host stack or heap memory per directory entry.

Text from CVE List

Affected versions 6

  • wasmtimeaffected: all versions before 36.0.17CVE List
  • wasmtimeunaffected: 36.0.17CVE List
  • wasmtimeaffected: 37.0.0 before 48.0.4CVE List
  • wasmtimeunaffected: 48.0.4CVE List
  • wasmtimeaffected: 49.0.0 before 49.0.2CVE List
  • wasmtimeunaffected: 49.0.2CVE List

References 2