CVE-2026-49839

jq is a command-line JSON processor. Prior to 1.8.2,` jq --rawfile` can turn a handled oversized-string error into invalid-state reuse and a real heap out-of-bounds write in assertion-disabled builds. When jv_load_file(raw=1) reads an attacker-controlled file, it repeatedly appends file chunks to the same jv string accumulator. Once jv_string_append_buf() returns jv_invalid_with_msg("String too long"), the raw-file loop does not stop. If the file contains at least one more byte, the next loop iteration appends a new chunk to an object that is already invalid. With assertions enabled this aborts in jvp_string_ptr(). With assertions disabled, the invalid object is interpreted as a string object and ASan reports heap-buffer-overflow. This vulnerability is fixed in 1.8.2.

CVSS v3 7.1 HIGH

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.2

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/jqlang/jq/security/advisories/GHSA-cfh2-vwfq-qfmm	Exploit Vendor Advisory
https://github.com/jqlang/jq/security/advisories/GHSA-cfh2-vwfq-qfmm	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:jqlang:jq:*:*:*:*:*:*:*:*

History

26 Jun 2026, 18:53

Type	Values Removed	Values Added
References	~~() https://github.com/jqlang/jq/security/advisories/GHSA-cfh2-vwfq-qfmm -~~	() https://github.com/jqlang/jq/security/advisories/GHSA-cfh2-vwfq-qfmm - Exploit, Vendor Advisory
CPE		cpe:2.3:a:jqlang:jq::::::::
First Time		Jqlang jq Jqlang

25 Jun 2026, 19:16

Type	Values Removed	Values Added
References	~~() https://github.com/jqlang/jq/security/advisories/GHSA-cfh2-vwfq-qfmm -~~	() https://github.com/jqlang/jq/security/advisories/GHSA-cfh2-vwfq-qfmm -

25 Jun 2026, 18:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-25 18:16

Updated : 2026-06-26 18:53

NVD link : CVE-2026-49839

Mitre link : CVE-2026-49839

CVE.ORG link : CVE-2026-49839

JSON object : View

Products Affected

jqlang

jq

CWE

CWE-787

Out-of-bounds Write

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