CVE-2026-43894

MEDIUM
MEDIUM Priority: 0.01 BB Relevance: 36/100
Published: 2026-05-11 Modified: 2026-10-26 First seen: 2026-10-29 Status: active

Attack Surface

Low Complexity No Interaction

CVSS Vector Breakdown

AV: Local
AC: Low
PR: Low
UI: None
S: Unchanged
C: None
I: None
A: High

Description

jq is a command-line JSON processor. In 1.8.1 and earlier, when decNumberFromString is given a number literal of INT_MAX-1 (2147483646) digits, the D2U() macro overflows during signed-int arithmetic. The wrapped negative value bypasses the heap-allocation size check, causes the function to use a 30-byte stack buffer, and then writes ≈715 million 16-bit units (≈1.4 GiB) at an offset 1.43 GiB below the stack frame. The written content is fully attacker-controlled (the parsed decimal digits, packed 3-per-unit).

Weakness Classification (1)

Affected Software (1)

VendorProductVersion
jqlang jq < 1.8.1

References & Advisories (1)

Bug Bounty Relevance

36 / 100
✓ Low complexity
✓ No user interaction

CVSS Score

5.5 / 10.0 v3.1
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS — Exploitation Probability

0.16%
Raw Score 0.001580
Percentile 4.9%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00158
2026-10-28
0.00158

Intelligence Sources

nvd ref →