Sandbox escape via unchecked funcref table allocation
Published Sep 12, 2026 · Updated Sep 12, 2026
Sandbox escape in WABT wasm2c through 1.0.41 allows attackers to execute code in the host process after a funcref allocation failure. wasm_rt_allocate_funcref_table() leaves table data null but retains the guest-declared size when calloc() fails, so bounds-checked table accesses resolve to absolute host addresses. Exploitation requires allocation failure, such as under a 32-bit address-space limit or memory pressure, and grants host-memory read and write access outside the sandbox.
Summary
What happened
Sandbox escape in WABT wasm2c through 1.0.41 allows attackers to execute code in the host process after a funcref allocation failure. wasm_rt_allocate_funcref_table() leaves table data null but retains the guest-declared size when calloc() fails, so bounds-checked table accesses resolve to absolute host addresses. Exploitation requires allocation failure, such as under a 32-bit address-space limit or memory pressure, and grants host-memory read and write access outside the sandbox.
The record
- CVE
- CVE-2026-90648
- Published
- Sep 12, 2026
- Updated
- Sep 12, 2026
- Vendor
- WebAssembly
- Product
- WABT
- Classifications
- Unavailable
- Attack vector
- Unavailable
- Privileges
- Unavailable
Timeline
How it unfolded
- Sep 12, 2026CVE publishedPublication date reported by the CVE source.
- Sep 12, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0 <=1.0.41
What conditions does exploitation require?
What is affected?
Published CVSS scores
No CVSS assessment is available in this record.
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
No sourced classifications are available.
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo