Buffer overflow in K2-Fsa Sherpa-Onnx
CVE-2026-108954
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.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
- K2-Fsa Sherpa-Onnx — versions 1.13.0, 1.13.1, 1.13.2
Weakness classification (CWE)
References
- github.com/k2-fsa/sherpa-onnx/ (product)
- github.com/k2-fsa/sherpa-onnx/issues/3983 (issue-tracking, exploit)
- github.com/k2-fsa/sherpa-onnx/issues/3983 (issue-tracking)
- vuldb.com/cve/CVE-2026-108954 (third-party-advisory)
- vuldb.com/submit/997824 (third-party-advisory)
- vuldb.com/vuln/416773 (technical-description, vdb-entry)
- vuldb.com/vuln/416773/cti (signature, permissions-required)
Frequently asked questions
- What is CVE-2026-108954?
- CVE-2026-108954 is a medium-severity vulnerability in K2-Fsa Sherpa-Onnx, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 6.3/10. Published 2026-10-13.
- How severe is CVE-2026-108954?
- Medium severity. CVSS v3 base score is 6.3 out of 10.