CVE-2026-108954 Details
Description
A vulnerability was found in k2-fsa sherpa-onnx up to 1.13.8. This issue affects the function OfflineTransducerGreedySearchDecoder::Decode of the file sherpa-onnx/csrc/offline-transducer-greedy-search-decoder.cc of the component Offline Transducer Greedy Search Decoder. The manipulation of the argument vocab_size results in buffer overflow. The attack can be launched remotely. The exploit has been made public and could be used. If only official model packs are used and they always keep metadata consistent with the joiner, the bug may not be reachable in normal supported usage. However, from a security and robustness standpoint, the code still contains the vulnerability because it trusts unvalidated model metadata and can be triggered by a malformed or tampered model pack.
A heap-based buffer overflow vulnerability has been identified in k2-fsa sherpa-onnx versions through 1.13.8. The issue arises in the Offline Transducer Greedy Search Decoder, specifically within the Decode function of the file sherpa-onnx/csrc/offline-transducer-greedy-search-decoder.cc. The vulnerability is triggered by a mismatch between the 'vocab_size' metadata in the decoder's ONNX file and the actual output width of the joiner ONNX file. This discrepancy allows for an out-of-bounds read and write, corrupting heap memory. The vulnerability can be exploited remotely by using a crafted model pack that takes advantage of this metadata inconsistency.
To address this vulnerability, it is recommended to validate the 'vocab_size' metadata against the joiner's output width before decoding. This can be done by comparing the values during the model pack loading process and rejecting any packs with inconsistencies. Until this patch is applied, users should verify the integrity of model packs from untrusted sources.
Metrics
CVSS 4.0 Severity and Vector Strings:
VolerionCVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
Volerion
Assessed Oct 13, 2026CISA-ADP
Assessed Oct 14, 2026References to Advisories, Solutions, and Tools
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| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/k2-fsa/sherpa-onnx/ | [email protected] | Source CodeVendor |
| https://github.com/k2-fsa/sherpa-onnx/issues/3983 | [email protected] | ExploitIssue TrackingTechnical DescriptionVendor |
| https://github.com/k2-fsa/sherpa-onnx/issues/3983#issuecomment-5871985324 | [email protected] | ExploitIssue TrackingTechnical DescriptionVendor |
| https://vuldb.com/cve/CVE-2026-108954 | [email protected] | AdvisoryPermission Required |
| https://vuldb.com/submit/997824 | [email protected] | Issue TrackingPermission Required |
| https://vuldb.com/vuln/416773 | [email protected] | AdvisoryPermission Required |
| https://vuldb.com/vuln/416773/cti | [email protected] | AdvisoryContent Wall |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-119 | Improper Restriction of Operations within the Bounds of a Memory Buffer | [email protected] |
| CWE-120 | Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| k2-fsa sherpa-onnx | <= 1.13.8 (semver) |
CPE
Remediation
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Change History
2 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Oct 14, 2026 | CVE Modified | CISA-ADP |
| Oct 13, 2026 | New CVE Received | [email protected] |