Buffer Overflow in Offline Transducer Greedy Search Decoder of k2-fsa Sherpa ONNX
CVE-2026-108954

5.3MEDIUM

Key Information:

Vendor

K2-fsa

Status
Sherpa-onnx
Vendor
CVE Published:
13 October 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-108954?

A buffer overflow vulnerability exists in the Offline Transducer Greedy Search Decoder of k2-fsa Sherpa ONNX up to version 1.13.8. It occurs due to the manipulation of the vocab_size argument within the Decode function. An attacker can exploit this vulnerability remotely by providing malformed or tampered model packs. While safe usage can mitigate risk when only official model packs with consistent metadata are employed, the underlying code remains vulnerable due to its reliance on unvalidated input, posing a significant security risk.

Affected Version(s)

sherpa-onnx 1.13.0

sherpa-onnx 1.13.1

sherpa-onnx 1.13.2

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-108954 - Proof of Concept

References

https://vuldb.com/vuln/416773
vdb-entrytechnical-description
https://vuldb.com/vuln/416773/cti
signaturepermissions-required
https://vuldb.com/cve/CVE-2026-108954
third-party-advisory

CVSS V4

Score:
5.3
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
Low
Availability:
Low
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
Unknown

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

Dem0 (VulDB User)
.