cvedb.io
CVE-2026-39956
MEDIUM · CVSS 6.1
EPSS exploitation probability: 0%
Published 2026-04-13T23:16:27.653 · Last modified 2026-06-17T10:42:48.533

Summary

jq is a command-line JSON processor. In commits after 69785bf77f86e2ea1b4a20ca86775916889e91c9, the _strindices builtin in jq's src/builtin.c passes its arguments directly to jv_string_indexes() without verifying they are strings, and jv_string_indexes() in src/jv.c relies solely on assert() checks that are stripped in release builds compiled with -DNDEBUG. This allows an attacker to crash jq trivially with input like _strindices(0), and by crafting a numeric value whose IEEE-754 bit pattern maps to a chosen pointer, achieve a controlled pointer dereference and limited memory read/probe primitive. Any deployment that evaluates untrusted jq filters against a release build is vulnerable. This issue has been patched in commit fdf8ef0f0810e3d365cdd5160de43db46f57ed03.

Affected products

jqlang — jq

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.