CVE-2026-39956

MEDIUMNVD 6.16.1—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 6.1 under NVD CVSS v3. EPSS exploit probability: 0.2%, top 93% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, nvd
Trending — 4 sources updated this weekElevated
6.1EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 6.1Exploit: Elevated riskExposed: 0

A fix is available — apply it.

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.

CVSS v3
6.1
EG Score
6.1(medium)
EG Risk
43(Track)
EG Risk 43/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity61% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
7%
KEV
Not listed

Published

April 13, 2026

Last Modified

September 4, 2026

Advisory Details (2)

Auto-updated Aug 2, 2026
🔬 Proof of concept available. Patch available. Sources: github_commit, github.
github Patch Available🟡 PoC Available

jq _strindices missing runtime type checks lead to crash and limited memory disclosure · Advisory · jqlang/jq · GitHub

https://github.com/jqlang/jq/security/advisories/GHSA-6gc3-3g9p-xx28
github_commit

commit fdf8ef0f0810 (jqlang/jq)

Fix landed in jqlang/jq commit fdf8ef0f0810 — awaiting tagged release

https://github.com/jqlang/jq/commit/fdf8ef0f0810e3d365cdd5160de43db46f57ed03

Vendor Advisories for CVE-2026-39956(2)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(3)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntujq (1.5+dfsg-1ubuntu0.1+esm4) @ xenial2026-06-14ubuntu
ubuntulibjq1 (1.8.1-4ubuntu2) @ resolute2026-06-14ubuntu
redhatjq-main-1.8.1-3.hum12026-04-16redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
jq1.6-2.1, 1.6-2.1+deb11u11.6-2.1+deb11u2—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
jq1.6-2.1, 1.6-2.1+deb12u11.6-2.1+deb12u2—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
jq1.7.1-6+deb13u11.7.1-6+deb13u2—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
jq1.8.0-1, 1.8.1-1, 1.8.1-2, 1.8.1-3, 1.8.1-41.8.1-5—

Weakness Classification(3)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Additional Vendor Advisories

(2)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 8× in last 7d / 40× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 162 total refreshes for this CVE.

  1. 2026-09-04 14:21 UTCEG score recompute
  2. 2026-09-04 14:21 UTCVendor advisory
  3. 2026-09-04 13:38 UTCEG score recompute
  4. 2026-09-04 13:38 UTCVendor advisory
  5. 2026-09-04 05:06 UTCEPSS rescore
  6. 2026-09-02 05:28 UTCOSV refresh
  7. 2026-08-30 19:17 UTCEPSS rescore
  8. 2026-08-30 01:22 UTCEPSS rescore
  9. 2026-08-28 21:41 UTCEPSS rescore
  10. 2026-08-27 14:25 UTCEPSS rescore
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  15. 2026-08-19 17:03 UTCEPSS rescore
  16. 2026-08-17 13:47 UTCEPSS rescore
  17. 2026-08-16 14:56 UTCEPSS rescore
  18. 2026-08-16 06:52 UTCEG score recompute
  19. 2026-08-16 06:52 UTCVendor advisory
  20. 2026-08-16 02:14 UTCEPSS rescore
  21. 2026-08-15 01:30 UTCEPSS rescore
  22. 2026-08-14 04:54 UTCEG score recompute
  23. 2026-08-14 04:54 UTCVendor advisory
  24. 2026-08-13 22:00 UTCEPSS rescore
  25. 2026-08-12 19:08 UTCEG score recompute
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  1. 2026-08-12 19:08 UTCVendor advisory
  2. 2026-08-12 13:51 UTCEPSS rescore
  3. 2026-08-11 13:43 UTCEPSS rescore
  4. 2026-08-11 07:35 UTCEG score recompute
  5. 2026-08-11 07:35 UTCVendor advisory
  6. 2026-08-11 00:00 UTCEPSS rescore
  7. 2026-08-10 05:56 UTCEG score recompute
  8. 2026-08-10 05:56 UTCVendor advisory
  9. 2026-08-09 13:46 UTCEPSS rescore
  10. 2026-08-09 04:17 UTCEG score recompute
  11. 2026-08-09 04:17 UTCVendor advisory
  12. 2026-08-08 16:37 UTCEPSS rescore
  13. 2026-08-07 13:55 UTCEG score recompute
  14. 2026-08-07 13:55 UTCVendor advisory
  15. 2026-08-06 13:46 UTCEPSS rescore
  16. 2026-08-05 23:32 UTCEG score recompute
  17. 2026-08-05 23:32 UTCVendor advisory
  18. 2026-08-05 19:17 UTCEPSS rescore
  19. 2026-08-04 15:10 UTCEPSS rescore
  20. 2026-08-04 10:38 UTCEPSS rescore
  21. 2026-08-03 21:47 UTCEG score recompute
  22. 2026-08-03 21:47 UTCVendor advisory
  23. 2026-08-03 10:36 UTCEPSS rescore
  24. 2026-08-02 13:32 UTCEG score recompute
  25. 2026-08-02 13:32 UTCVendor advisory
  26. 2026-08-02 02:27 UTCEPSS rescore
  27. 2026-08-01 04:16 UTCEPSS rescore
  28. 2026-07-30 16:28 UTCEPSS rescore
  29. 2026-07-30 01:30 UTCEPSS rescore
  30. 2026-07-27 14:13 UTCEPSS rescore
  31. 2026-07-26 14:54 UTCEPSS rescore
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  37. 2026-07-23 14:18 UTCEPSS rescore
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  39. 2026-07-23 03:10 UTCEG score recompute
  40. 2026-07-22 14:08 UTCEPSS rescore
  41. 2026-07-21 15:24 UTCEPSS rescore
  42. 2026-07-20 17:08 UTCEPSS rescore
  43. 2026-07-20 11:04 UTCOSV refresh
  44. 2026-07-19 14:31 UTCEPSS rescore
  45. 2026-07-19 02:29 UTCEPSS rescore
  46. 2026-07-18 10:04 UTCEPSS rescore
  47. 2026-07-16 17:03 UTCEPSS rescore
  48. 2026-07-15 16:57 UTCEPSS rescore
  49. 2026-07-15 16:57 UTCEPSS rescore
  50. 2026-07-15 02:00 UTCEPSS rescore
  51. 2026-07-13 22:30 UTCEPSS rescore
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  54. 2026-07-12 05:46 UTCEPSS rescore
  55. 2026-07-11 08:27 UTCEPSS rescore
  56. 2026-07-09 19:10 UTCEPSS rescore
  57. 2026-07-08 15:15 UTCEPSS rescore
  58. 2026-07-07 13:46 UTCEPSS rescore
  59. 2026-07-06 16:27 UTCEPSS rescore
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  65. 2026-07-01 15:06 UTCEPSS rescore
  66. 2026-06-30 23:22 UTCEPSS rescore
  67. 2026-06-29 14:06 UTCEPSS rescore
  68. 2026-06-28 14:07 UTCEPSS rescore
  69. 2026-06-28 04:56 UTCEPSS rescore
  70. 2026-06-27 03:08 UTCEPSS rescore
  71. 2026-06-25 13:49 UTCEPSS rescore
  72. 2026-06-25 13:49 UTCEPSS rescore
  73. 2026-06-24 14:05 UTCEPSS rescore
  74. 2026-06-23 21:33 UTCEPSS rescore
  75. 2026-06-22 14:25 UTCEPSS rescore

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-39956?
CVE-2026-39956 is a medium vulnerability published on April 13, 2026. 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 jvstringindexes() without verifying they are strings, and jvstringindexes() in src/jv.c relies solely on assert() checks that are stripped in release builds…
When was CVE-2026-39956 disclosed?
CVE-2026-39956 was first published in the National Vulnerability Database on April 13, 2026, with the most recent update on September 4, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-39956 actively exploited?
CVE-2026-39956 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 93.0% of all scored CVEs.
What is the CVSS score of CVE-2026-39956?
CVE-2026-39956 has a CVSS v3 base score of 6.1 (NVD).
How do I remediate CVE-2026-39956?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-39956, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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