CVE-2026-87877

HIGHPre-NVD 7.77.7—
EchelonGraph scoreHIGH confidence

Score 7.7 from GitHub Security Advisory (severity: HIGH) published 2026-09-09. A secondary CVSS source baseline 7.7; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
7.7EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.2%CVSS: 7.7Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

zstd-jni versions before 1.5.7-14 fail to validate closed state in setDict, setLongMax, setLevel and setRefMultipleDDicts methods of stream classes. Attackers can call these methods on closed streams to write through freed native pointers, corrupting unrelated objects or crashing the JVM.

CVSS v3
7.7
EG Score
7.7HIGHhigh confidence
EG Risk
39
EG Risk 39/100CISA SSVC

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
Severity77% × 45%
Exploitation0% × 40%
Automatability30% × 15%
CISA SSVC: Track at low or medium mission impact; Track or Attend at high (mission-essential systems).
Action: A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
EPSS PROB
0.2%
EPSS %ILE
9th
KEV
Not listed

CISA SSVCTrack at low or medium mission impact; Track or Attend at high (mission-essential systems).

A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation none (no KEV listing, exploit record or EPSS ≥ 50%) · Automatable unknown (not published for this CVE) · Technical impact partial (CVSS below 9.0). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table

Published

September 9, 2026

Last Modified

September 9, 2026

Advisory Details (8)

Auto-updated Sep 9, 2026
🔬 Proof of concept available. Patch available. Sources: github, github_commit.
generic

zstd-jni 1.3.8-4 through 1.5.7-13 Use-After-Free via Setters Called After close() | Advisories | VulnCheck

https://www.vulncheck.com/advisories/zstd-jni-1.3.8-4-through-1.5.7-13-use-after-free-via-setters-called-after-close
generic

GitHub - luben/zstd-jni: JNI binding for Zstd · GitHub

https://github.com/luben/zstd-jni
github_commit

commit 0827ed02551b (luben/zstd-jni)

Fix landed in luben/zstd-jni commit 0827ed02551b — awaiting tagged release

https://github.com/luben/zstd-jni/commit/0827ed02551bbd8d6f8e4bbff99d83bf50f91938
generic

zstd-jni/src/main/java/com/github/luben/zstd/ZstdInputStreamNoFinalizer.java at v1.5.7-13 · luben/zstd-jni · GitHub

https://github.com/luben/zstd-jni/blob/v1.5.7-13/src/main/java/com/github/luben/zstd/ZstdInputStreamNoFinalizer.java
generic

zstd-jni/src/main/java/com/github/luben/zstd/BaseZstdBufferDecompressingStreamNoFinalizer.java at v1.5.7-13 · luben/zstd-jni · GitHub

https://github.com/luben/zstd-jni/blob/v1.5.7-13/src/main/java/com/github/luben/zstd/BaseZstdBufferDecompressingStreamNoFinalizer.java
github_commit

commit 393d7311766a (luben/zstd-jni)

Fix landed in luben/zstd-jni commit 393d7311766a — awaiting tagged release

https://github.com/luben/zstd-jni/commit/393d7311766abbc285b149302c0fe1f94b16d555
github_commit

commit f38f9a156311 (luben/zstd-jni)

Fix landed in luben/zstd-jni commit f38f9a156311 — awaiting tagged release

https://github.com/luben/zstd-jni/commit/f38f9a1563113d96d0fc38baee543f7457dd8a8e
github Patch Available🟡 PoC Available

Use-After-Free via Missing Closed-State Check on setDict/setLongMax/setLevel · Advisory · luben/zstd-jni · GitHub

https://github.com/luben/zstd-jni/security/advisories/GHSA-2jw3-mg7f-vw4q

Vendor Advisories for CVE-2026-87877(2)

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

Patch Availability(1)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
redhatzstd-jni2026-09-24redhat

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

(3 across 3 ecosystems)
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
zstd-jni-java1.5.2-5+ds-3 ... 1.5.4-2+ds-3~exp4 (12 versions)
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
zstd-jni-java1.5.2-5+ds-7 ... 1.5.4-2+ds-3~exp4 (8 versions)
  • every version on: no fix on record
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
zstd-jni-java1.5.2-5+ds-7 ... 1.5.4-2+ds-3~exp4 (8 versions)
  • every version on: no fix on record
—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 40× in last 7d / 120× 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 120 total refreshes for this CVE.

  1. 2026-10-05 07:29 UTCEG score recompute
  2. 2026-10-05 07:29 UTCVendor advisory
  3. 2026-10-05 07:29 UTCGHSA enrichment
  4. 2026-10-04 23:22 UTCEPSS rescore
  5. 2026-10-04 19:22 UTCVendor advisory
  6. 2026-10-04 19:22 UTCGHSA enrichment
  7. 2026-10-04 07:16 UTCVendor advisory
  8. 2026-10-04 07:16 UTCGHSA enrichment
  9. 2026-10-03 19:10 UTCEG score recompute
  10. 2026-10-03 19:10 UTCVendor advisory
  11. 2026-10-03 19:10 UTCGHSA enrichment
  12. 2026-10-03 06:02 UTCEG score recompute
  13. 2026-10-03 06:02 UTCVendor advisory
  14. 2026-10-03 06:02 UTCGHSA enrichment
  15. 2026-10-02 17:55 UTCVendor advisory
  16. 2026-10-02 17:55 UTCGHSA enrichment
  17. 2026-10-02 05:49 UTCEG score recompute
  18. 2026-10-02 05:49 UTCVendor advisory
  19. 2026-10-02 05:49 UTCGHSA enrichment
  20. 2026-10-01 19:51 UTCEPSS rescore
  21. 2026-10-01 17:33 UTCVendor advisory
  22. 2026-10-01 17:33 UTCGHSA enrichment
  23. 2026-10-01 05:26 UTCVendor advisory
  24. 2026-10-01 05:26 UTCGHSA enrichment
  25. 2026-09-30 17:19 UTCEG score recompute
Show 75 more
  1. 2026-09-30 17:19 UTCVendor advisory
  2. 2026-09-30 17:19 UTCGHSA enrichment
  3. 2026-09-30 15:04 UTCEPSS rescore
  4. 2026-09-30 04:14 UTCVendor advisory
  5. 2026-09-30 04:14 UTCGHSA enrichment
  6. 2026-09-29 15:55 UTCEG score recompute
  7. 2026-09-29 15:55 UTCVendor advisory
  8. 2026-09-29 15:55 UTCGHSA enrichment
  9. 2026-09-29 03:48 UTCEG score recompute
  10. 2026-09-29 03:48 UTCVendor advisory
  11. 2026-09-29 03:48 UTCGHSA enrichment
  12. 2026-09-28 15:41 UTCEG score recompute
  13. 2026-09-28 15:41 UTCVendor advisory
  14. 2026-09-28 15:41 UTCGHSA enrichment
  15. 2026-09-28 13:52 UTCEPSS rescore
  16. 2026-09-28 03:27 UTCVendor advisory
  17. 2026-09-28 03:27 UTCGHSA enrichment
  18. 2026-09-27 15:21 UTCEG score recompute
  19. 2026-09-27 15:21 UTCVendor advisory
  20. 2026-09-27 15:21 UTCGHSA enrichment
  21. 2026-09-27 13:48 UTCEPSS rescore
  22. 2026-09-27 03:12 UTCEG score recompute
  23. 2026-09-27 03:12 UTCVendor advisory
  24. 2026-09-27 03:12 UTCGHSA enrichment
  25. 2026-09-26 15:59 UTCEPSS rescore
  26. 2026-09-26 15:03 UTCVendor advisory
  27. 2026-09-26 15:03 UTCGHSA enrichment
  28. 2026-09-26 01:49 UTCEG score recompute
  29. 2026-09-26 01:49 UTCVendor advisory
  30. 2026-09-26 01:49 UTCGHSA enrichment
  31. 2026-09-25 13:38 UTCVendor advisory
  32. 2026-09-25 13:38 UTCGHSA enrichment
  33. 2026-09-25 01:28 UTCEG score recompute
  34. 2026-09-25 01:28 UTCGHSA enrichment
  35. 2026-09-24 14:04 UTCEPSS rescore
  36. 2026-09-24 13:21 UTCGHSA enrichment
  37. 2026-09-24 01:14 UTCEG score recompute
  38. 2026-09-24 01:14 UTCGHSA enrichment
  39. 2026-09-23 17:54 UTCEPSS rescore
  40. 2026-09-23 13:08 UTCGHSA enrichment
  41. 2026-09-23 01:01 UTCEG score recompute
  42. 2026-09-23 01:01 UTCGHSA enrichment
  43. 2026-09-22 16:01 UTCEPSS rescore
  44. 2026-09-22 12:54 UTCGHSA enrichment
  45. 2026-09-22 00:48 UTCEG score recompute
  46. 2026-09-22 00:48 UTCGHSA enrichment
  47. 2026-09-21 21:09 UTCEPSS rescore
  48. 2026-09-21 12:41 UTCGHSA enrichment
  49. 2026-09-21 00:35 UTCEG score recompute
  50. 2026-09-21 00:35 UTCGHSA enrichment
  51. 2026-09-20 20:16 UTCEPSS rescore
  52. 2026-09-20 12:29 UTCGHSA enrichment
  53. 2026-09-20 00:20 UTCEG score recompute
  54. 2026-09-20 00:20 UTCGHSA enrichment
  55. 2026-09-19 12:13 UTCGHSA enrichment
  56. 2026-09-19 00:07 UTCEG score recompute
  57. 2026-09-19 00:07 UTCGHSA enrichment
  58. 2026-09-18 19:28 UTCEPSS rescore
  59. 2026-09-18 12:01 UTCGHSA enrichment
  60. 2026-09-17 23:54 UTCEG score recompute
  61. 2026-09-17 23:54 UTCGHSA enrichment
  62. 2026-09-17 19:32 UTCEPSS rescore
  63. 2026-09-17 10:34 UTCGHSA enrichment
  64. 2026-09-16 22:24 UTCEG score recompute
  65. 2026-09-16 22:24 UTCGHSA enrichment
  66. 2026-09-16 14:09 UTCEPSS rescore
  67. 2026-09-16 10:00 UTCEG score recompute
  68. 2026-09-16 09:59 UTCGHSA enrichment
  69. 2026-09-16 05:15 UTCEPSS rescore
  70. 2026-09-15 21:53 UTCGHSA enrichment
  71. 2026-09-15 09:47 UTCEG score recompute
  72. 2026-09-15 09:47 UTCGHSA enrichment
  73. 2026-09-15 03:12 UTCEPSS rescore
  74. 2026-09-14 21:41 UTCGHSA enrichment
  75. 2026-09-14 09:35 UTCGHSA enrichment

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-87877?
CVE-2026-87877 is a high vulnerability published on September 9, 2026. zstd-jni versions before 1.5.7-14 fail to validate closed state in setDict, setLongMax, setLevel and setRefMultipleDDicts methods of stream classes. Attackers can call these methods on closed streams to write through freed native pointers, corrupting unrelated objects or crashing the JVM.
When was CVE-2026-87877 disclosed?
CVE-2026-87877 was first published on September 9, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-87877 actively exploited?
CVE-2026-87877 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.2% probability of exploitation in the next 30 days (9th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-87877?
CVE-2026-87877 has a CVSS base score of 7.7 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-87877?
A fix for CVE-2026-87877 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-87877 are linked in the Vendor Advisories panel on this page.

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