SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-33947

An attacker can supply a JSON document containing a flat array of ~65,000 integers (~200 KB) that, when used as a path argument by a trusted jq filter, exhausts the C call stack and crashes the process with a segmentation fault (SIGSEGV).

MEDIUM 5.5EPSS 0.23%

Does this matter?

Lower severity and a low EPSS score (0.23%). Track it; it rarely justifies an emergency change on its own.

Description

jq is a command-line JSON processor. In versions 1.8.1 and below, functions jv_setpath(), jv_getpath(), and delpaths_sorted() in jq's src/jv_aux.c use unbounded recursion whose depth is controlled by the length of a caller-supplied path array, with no depth limit enforced. An attacker can supply a JSON document containing a flat array of ~65,000 integers (~200 KB) that, when used as a path argument by a trusted jq filter, exhausts the C call stack and crashes the process with a segmentation fault (SIGSEGV). This bypass works because the existing MAX_PARSING_DEPTH (10,000) limit only protects the JSON parser, not runtime path operations where arrays can be programmatically constructed to arbitrary lengths. The impact is denial of service (unrecoverable crash) affecting any application or service that processes untrusted JSON input through jq's setpath, getpath, or delpaths builtins. This issue has been addressed in commit fb59f1491058d58bdc3e8dd28f1773d1ac690a1f.

CVSS 3.1
5.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS
0.23% probability · 14th percentile
CISA KEV
Not listed
Weakness
CWE-674
Affected
jqlang/jq
Source
security-advisories@github.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.