Out-of-bounds write in jq - CVE-2026-43894
Published: May 11, 2026
Vulnerability identifier: #VU130926
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-43894
CWE-ID: CWE-787
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: stedolan (Stephen Dolan)
Affected software:
jq
jq
Detailed vulnerability description
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to out-of-bounds write in decNumber D2U() macro in decNumberFromString when processing an extremely large decimal string via tonumber. A remote attacker can supply a specially crafted number string to cause a denial of service.
The issue is triggered by signed integer overflow and is reachable through tonumber on a string built via the multiplication operator rather than through raw JSON number parsing.
How to mitigate CVE-2026-43894
Cybersecurity Help is currently unaware of any official solution to address this vulnerability.