CVE-2026-39979

jq is a command-line JSON processor. In commits before 2f09060afab23fe9390cce7cb860b10416e1bf5f, the jv_parse_sized() API in libjq accepts a counted buffer with an explicit length parameter, but its error-handling path formats the input buffer using %s in jv_string_fmt(), which reads until a NUL terminator is found rather than respecting the caller-supplied length. This means that when malformed JSON is passed in a non-NUL-terminated buffer, the error construction logic performs an out-of-bounds read past the end of the buffer. The vulnerability is reachable by any libjq consumer calling jv_parse_sized() with untrusted input, and depending on memory layout, can result in memory disclosure or process termination. The issue has been patched in commit 2f09060afab23fe9390cce7cb860b10416e1bf5f.
References
Link Resource
https://github.com/jqlang/jq/commit/2f09060afab23fe9390cce7cb860b10416e1bf5f Patch
https://github.com/jqlang/jq/security/advisories/GHSA-2hhh-px8h-355p Exploit Vendor Advisory
https://access.redhat.com/errata/RHSA-2026:16252
https://access.redhat.com/errata/RHSA-2026:16692
https://access.redhat.com/errata/RHSA-2026:16693
https://access.redhat.com/errata/RHSA-2026:18040
https://access.redhat.com/errata/RHSA-2026:18042
https://access.redhat.com/errata/RHSA-2026:18043
https://access.redhat.com/errata/RHSA-2026:18044
https://access.redhat.com/errata/RHSA-2026:18045
https://access.redhat.com/errata/RHSA-2026:18046
https://access.redhat.com/errata/RHSA-2026:18047
https://access.redhat.com/errata/RHSA-2026:18048
https://access.redhat.com/errata/RHSA-2026:19151
https://access.redhat.com/errata/RHSA-2026:19365
https://access.redhat.com/errata/RHSA-2026:23233
https://access.redhat.com/errata/RHSA-2026:23245
https://access.redhat.com/errata/RHSA-2026:25044
https://access.redhat.com/errata/RHSA-2026:25096
https://access.redhat.com/errata/RHSA-2026:25181
https://access.redhat.com/errata/RHSA-2026:26528
https://access.redhat.com/errata/RHSA-2026:26542
https://access.redhat.com/errata/RHSA-2026:28887
https://access.redhat.com/errata/RHSA-2026:30078
https://access.redhat.com/errata/RHSA-2026:30087
https://access.redhat.com/errata/RHSA-2026:30088
https://access.redhat.com/errata/RHSA-2026:30089
https://access.redhat.com/errata/RHSA-2026:34098
https://access.redhat.com/errata/RHSA-2026:8579
https://access.redhat.com/security/cve/CVE-2026-39979
https://bugzilla.redhat.com/show_bug.cgi?id=2458077
https://github.com/jqlang/jq/security/advisories/GHSA-2hhh-px8h-355p Exploit Vendor Advisory
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-39979.json
Configurations

Configuration 1 (hide)

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

History

10 Jul 2026, 12:16

Type Values Removed Values Added
References
  • () https://access.redhat.com/errata/RHSA-2026:34098 -

02 Jul 2026, 12:17

Type Values Removed Values Added
References
  • () https://access.redhat.com/errata/RHSA-2026:28887 -

30 Jun 2026, 03:19

Type Values Removed Values Added
References
  • () https://access.redhat.com/errata/RHSA-2026:16252 -
  • () https://access.redhat.com/errata/RHSA-2026:16692 -
  • () https://access.redhat.com/errata/RHSA-2026:16693 -
  • () https://access.redhat.com/errata/RHSA-2026:18040 -
  • () https://access.redhat.com/errata/RHSA-2026:18042 -
  • () https://access.redhat.com/errata/RHSA-2026:18043 -
  • () https://access.redhat.com/errata/RHSA-2026:18044 -
  • () https://access.redhat.com/errata/RHSA-2026:18045 -
  • () https://access.redhat.com/errata/RHSA-2026:18046 -
  • () https://access.redhat.com/errata/RHSA-2026:18047 -
  • () https://access.redhat.com/errata/RHSA-2026:18048 -
  • () https://access.redhat.com/errata/RHSA-2026:19151 -
  • () https://access.redhat.com/errata/RHSA-2026:19365 -
  • () https://access.redhat.com/errata/RHSA-2026:23233 -
  • () https://access.redhat.com/errata/RHSA-2026:23245 -
  • () https://access.redhat.com/errata/RHSA-2026:25044 -
  • () https://access.redhat.com/errata/RHSA-2026:25096 -
  • () https://access.redhat.com/errata/RHSA-2026:25181 -
  • () https://access.redhat.com/errata/RHSA-2026:26528 -
  • () https://access.redhat.com/errata/RHSA-2026:26542 -
  • () https://access.redhat.com/errata/RHSA-2026:30078 -
  • () https://access.redhat.com/errata/RHSA-2026:30087 -
  • () https://access.redhat.com/errata/RHSA-2026:30088 -
  • () https://access.redhat.com/errata/RHSA-2026:30089 -
  • () https://access.redhat.com/errata/RHSA-2026:8579 -
  • () https://access.redhat.com/security/cve/CVE-2026-39979 -
  • () https://bugzilla.redhat.com/show_bug.cgi?id=2458077 -
  • () https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-39979.json -

23 Apr 2026, 16:50

Type Values Removed Values Added
References () https://github.com/jqlang/jq/commit/2f09060afab23fe9390cce7cb860b10416e1bf5f - () https://github.com/jqlang/jq/commit/2f09060afab23fe9390cce7cb860b10416e1bf5f - Patch
References () https://github.com/jqlang/jq/security/advisories/GHSA-2hhh-px8h-355p - () https://github.com/jqlang/jq/security/advisories/GHSA-2hhh-px8h-355p - Exploit, Vendor Advisory
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 6.5
First Time Jqlang
Jqlang jq
CPE cpe:2.3:a:jqlang:jq:*:*:*:*:*:*:*:*

14 Apr 2026, 15:16

Type Values Removed Values Added
References () https://github.com/jqlang/jq/security/advisories/GHSA-2hhh-px8h-355p - () https://github.com/jqlang/jq/security/advisories/GHSA-2hhh-px8h-355p -

13 Apr 2026, 23:16

Type Values Removed Values Added
New CVE

Information

Published : 2026-04-13 23:16

Updated : 2026-07-15 02:20


NVD link : CVE-2026-39979

Mitre link : CVE-2026-39979

CVE.ORG link : CVE-2026-39979


JSON object : View

Products Affected

jqlang

  • jq
CWE
CWE-125

Out-of-bounds Read