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CVE-2026-39956 (GCVE-0-2026-39956)

Vulnerability from cvelistv5 – Published: 2026-04-13 22:10 – Updated: 2026-09-04 13:29
VLAI
Title
jq: Missing runtime type checks for _strindices lead to crash and limited memory disclosure
Summary
jq is a command-line JSON processor. Prior to version 1.8.2, 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, which is part of version 1.8.2.
Severity
6.1 (Medium)
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-14 15:34 UTC
CWE
  • CWE-125 - Out-of-bounds Read
  • CWE-476 - NULL Pointer Dereference
  • CWE-843 - Access of Resource Using Incompatible Type ('Type Confusion')
Assigner
References
Impacted products
Vendor Product Version CPE status
jqlang jq Affected: < 1.8.2
guessed Create a notification for this product.
Show details on NVD website
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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