CVE-2021-41498Network attack vector

Service crash via unterminated JACK client name

Published Dec 17, 2021 · Updated Aug 4, 2024

Buffer overflow in Pyo before 1.0.4 allows remote attackers to crash the JACK-backed audio server via an overlong client name. In Server_jack_init in src/engine/ad_jack.c, strncpy copies up to 31 bytes into an uninitialized 32-byte client_name buffer without guaranteeing a null terminator before jack_client_open reads it. Exploitation requires control of the server name and execution of the JACK backend initialization path, and the documented consequence is denial of service only.

CVSS severity7.5
High
EPSS probability1.07%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Buffer overflow in Pyo before 1.0.4 allows remote attackers to crash the JACK-backed audio server via an overlong client name. In Server_jack_init in src/engine/ad_jack.c, strncpy copies up to 31 bytes into an uninitialized 32-byte client_name buffer without guaranteeing a null terminator before jack_client_open reads it. Exploitation requires control of the server name and execution of the JACK backend initialization path, and the documented consequence is denial of service only.

The record

CVE
CVE-2021-41498
Published
Dec 17, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-120, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 17, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

8.7GitHub Advisory DatabaseCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
5.0NVDAV:N/AC:L/Au:N/C:N/I:N/A:P
7.5NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
T1499.004Endpoint Denial of Service: Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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