AEGLIX vulnerability intelligence
CVE-2026-34988
LOW · CVSS 2.3 · Analyzed
Published: 2026-04-09 · Updated: 2026-10-26 · Source: NVD
Stored catalog record
Source record retrieved 2026-10-28T10:18:42.429295+00:00. Scheduled imports handle updates; this page does not assert that the provider was queried just now.
Vulnerability overview
Wasmtime is a runtime for WebAssembly. From 28.0.0 to before 36.0.7, 42.0.2, and 43.0.1, Wasmtime's implementation of its pooling allocator contains a bug where in certain configurations the contents of linear memory can be leaked from one instance to the next. The implementation of resetting the virtual memory permissions for linear memory used the wrong predicate to determine if resetting was necessary, where the compilation process used a different predicate. This divergence meant that the pooling allocator incorrectly deduced at runtime that resetting virtual memory permissions was not necessary while compile-time determine that virtual memory could be relied upon. The pooling allocator must be in use, Config::memory_guard_size configuration option must be 0, Config::memory_reservation configuration must be less than 4GiB, and pooling allocator must be configured with max_memory_size the same as the memory_reservation value in order to exploit this vulnerability. If all of these conditions are applicable then when a linear memory is reused the VM permissions of the previous iteration are not reset. This means that the compiled code, which is assuming out-of-bounds loads will segfault, will not actually segfault and can read the previous contents of linear memory if it was previously mapped. This represents a data leakage vulnerability between guest WebAssembly instances which breaks WebAssembly's semantics and additionally breaks the sandbox that Wasmtime provides. Wasmtime is not vulnerable to this issue with its default settings, nor with the default settings of the pooling allocator, but embeddings are still allowed to configure these values to cause this vulnerability. This vulnerability is fixed in 36.0.7, 42.0.2, and 43.0.1.
Patch review priority
Assess exposure and vendor guidance
- No higher-priority signal is available in the current stored evidence.
FIRST EPSS: 0.29% · percentile 21.0 · score date 2026-10-27.
EPSS estimates probability of exploitation in the next 30 days. It does not measure your exposure or prove exploitation. The elevated threshold is 10%; CISA KEV takes precedence. About FIRST EPSS ↗
Severity and scoring
- CVSS score
- 2.3 · LOW
- CVSS version
- 4.0
- CVSS vector
- CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:L/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
- Weaknesses
- CWE-119
CVSS measures technical severity; it does not establish whether this vulnerability is being exploited in your environment.
Known exploitation and remediation
Not listed in the CISA catalog retrieved for this record. This does not establish that exploitation has not occurred.
Verify affected versions and patch availability in the vendor advisory before making changes.
Affected products and versions
cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:rust:*:*
From (inclusive): 28.0.0
Before (exclusive): 36.0.7
cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:rust:*:*
From (inclusive): 37.0.0
Before (exclusive): 42.0.2
cpe:2.3:a:bytecodealliance:wasmtime:43.0.0:*:*:*:*:rust:*:*
These are NVD CPE applicability entries. Some products depend on configuration conditions; consult the official record to confirm applicability.
Advisories and references
- https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-6wgr-89rj-399p
Mitigation · Vendor Advisory