CVE-2026-84361

HIGHPre-NVD 7.77.7—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.7 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.5%, top 57% 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, secondary
Trending — 3 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: 1%CVSS: 7.7Exploit: None knownExposed: 0

A fix is available — apply it.

Composer is a dependency Manager for the PHP language. From 1.0 until 2.2.30 and 2.10.3, a malicious dependency package from a custom Composer repository or an untrusted composer.lock file could set source.type to perforce and source.url to an rsh: or jsh: P4PORT value. When the Perforce p4 client was installed and Composer installed the package from source through composer install or composer update, including --prefer-source, Composer\Util\Perforce passed the address to p4 without validation, causing p4 to run a local command with the privileges of the user or CI account. Packagist.org does not permit Perforce source metadata. This issue is fixed in versions 2.2.30 and 2.10.3.

CVSS v3
7.7
EG Score
7.7(medium)
EG Risk
35(Track)
EG Risk 35/100SSVC: 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
Severity77% × 45%
Exploitation1% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
43%
KEV
Not listed

Published

September 1, 2026

Last Modified

September 9, 2026

Advisory Details (5)

Auto-updated Sep 1, 2026
Patch available. Sources: github, github_commit, github_release.
github_release Patch Available

2.2.30

Patch available: composer/composer 2.2.30

https://github.com/composer/composer/releases/tag/2.2.30
github_release Patch Available

2.10.3

Patch available: composer/composer 2.10.3

https://github.com/composer/composer/releases/tag/2.10.3
github_commit Patch Available

commit 199ad81a9cc6 (composer/composer)

Patch available: composer/composer 2.2.30 (contains commit 199ad81a9cc6)

https://github.com/composer/composer/commit/199ad81a9cc6a2a5164ad79a8da26b2e19e521af
github_commit Patch Available

commit 0aac50528e83 (composer/composer)

Patch available: composer/composer 2.10.3 (contains commit 0aac50528e83)

https://github.com/composer/composer/commit/0aac50528e83ed635cf788333635897469440220
github Patch Available

Composer arbitrary command execution via a malicious package's Perforce source URL · Advisory · composer/composer · GitHub

https://github.com/composer/composer/security/advisories/GHSA-rvx4-ffvw-m9q3

Vendor Advisories for CVE-2026-84361(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 / EcosystemFixed in / PatchReleasedSource
redhatcomposer-main-2.10.3-1.hum12026-09-03redhat

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:12(1)
PackageVulnerable rangeFixed inDependents
composer2.10.0-1 ... 2.9.8-1 (57 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
composer2.10.0-1 ... 2.9.8-1 (26 versions)——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
composer2.10.0-1 ... 2.9.8-1 (22 versions)2.10.3-1—
Packagist(1)
PackageVulnerable rangeFixed inDependents
composer/composer1.0.0 ... 2.2.9 (163 versions)2.2.30—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 28× in last 7d / 90× 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.

  1. 2026-09-25 09:36 UTCVendor advisory
  2. 2026-09-24 22:01 UTCEG score recompute
  3. 2026-09-24 22:01 UTCVendor advisory
  4. 2026-09-24 14:04 UTCEPSS rescore
  5. 2026-09-24 09:15 UTCVendor advisory
  6. 2026-09-23 21:41 UTCEG score recompute
  7. 2026-09-23 21:41 UTCVendor advisory
  8. 2026-09-23 17:54 UTCEPSS rescore
  9. 2026-09-23 10:06 UTCVendor advisory
  10. 2026-09-22 22:31 UTCEG score recompute
  11. 2026-09-22 22:31 UTCVendor advisory
  12. 2026-09-22 16:01 UTCEPSS rescore
  13. 2026-09-22 10:51 UTCVendor advisory
  14. 2026-09-21 23:17 UTCEG score recompute
  15. 2026-09-21 23:17 UTCVendor advisory
  16. 2026-09-21 21:09 UTCEPSS rescore
  17. 2026-09-21 11:42 UTCVendor advisory
  18. 2026-09-21 00:07 UTCEG score recompute
  19. 2026-09-21 00:07 UTCVendor advisory
  20. 2026-09-20 20:16 UTCEPSS rescore
  21. 2026-09-20 12:33 UTCVendor advisory
  22. 2026-09-20 00:41 UTCEG score recompute
  23. 2026-09-20 00:41 UTCVendor advisory
  24. 2026-09-19 13:06 UTCVendor advisory
  25. 2026-09-19 01:31 UTCEG score recompute
Show 65 more
  1. 2026-09-19 01:31 UTCVendor advisory
  2. 2026-09-18 19:28 UTCEPSS rescore
  3. 2026-09-18 13:57 UTCVendor advisory
  4. 2026-09-18 02:22 UTCEG score recompute
  5. 2026-09-18 02:22 UTCVendor advisory
  6. 2026-09-17 19:32 UTCEPSS rescore
  7. 2026-09-17 14:47 UTCVendor advisory
  8. 2026-09-17 03:12 UTCVendor advisory
  9. 2026-09-16 15:37 UTCEG score recompute
  10. 2026-09-16 15:37 UTCVendor advisory
  11. 2026-09-16 14:09 UTCEPSS rescore
  12. 2026-09-16 05:15 UTCEPSS rescore
  13. 2026-09-16 03:44 UTCVendor advisory
  14. 2026-09-15 16:09 UTCVendor advisory
  15. 2026-09-15 04:34 UTCEG score recompute
  16. 2026-09-15 04:34 UTCVendor advisory
  17. 2026-09-15 03:12 UTCEPSS rescore
  18. 2026-09-15 03:12 UTCEPSS rescore
  19. 2026-09-14 16:59 UTCVendor advisory
  20. 2026-09-14 05:24 UTCVendor advisory
  21. 2026-09-13 17:50 UTCEG score recompute
  22. 2026-09-13 17:50 UTCVendor advisory
  23. 2026-09-13 06:15 UTCVendor advisory
  24. 2026-09-12 18:41 UTCEG score recompute
  25. 2026-09-12 18:41 UTCVendor advisory
  26. 2026-09-12 07:06 UTCVendor advisory
  27. 2026-09-11 19:31 UTCEG score recompute
  28. 2026-09-11 19:31 UTCVendor advisory
  29. 2026-09-11 14:53 UTCEPSS rescore
  30. 2026-09-11 14:53 UTCEPSS rescore
  31. 2026-09-11 07:56 UTCVendor advisory
  32. 2026-09-10 20:21 UTCEG score recompute
  33. 2026-09-10 20:21 UTCVendor advisory
  34. 2026-09-10 08:46 UTCVendor advisory
  35. 2026-09-09 21:11 UTCVendor advisory
  36. 2026-09-09 10:55 UTCVendor advisory
  37. 2026-09-08 23:20 UTCEG score recompute
  38. 2026-09-08 23:20 UTCVendor advisory
  39. 2026-09-08 22:01 UTCEPSS rescore
  40. 2026-09-08 10:01 UTCVendor advisory
  41. 2026-09-07 21:31 UTCEG score recompute
  42. 2026-09-07 21:31 UTCVendor advisory
  43. 2026-09-07 09:57 UTCVendor advisory
  44. 2026-09-06 22:22 UTCEG score recompute
  45. 2026-09-06 22:22 UTCVendor advisory
  46. 2026-09-06 13:48 UTCEPSS rescore
  47. 2026-09-06 10:46 UTCVendor advisory
  48. 2026-09-05 23:11 UTCEG score recompute
  49. 2026-09-05 23:11 UTCVendor advisory
  50. 2026-09-05 15:31 UTCEPSS rescore
  51. 2026-09-05 11:36 UTCVendor advisory
  52. 2026-09-05 00:02 UTCEG score recompute
  53. 2026-09-05 00:02 UTCVendor advisory
  54. 2026-09-04 12:27 UTCEG score recompute
  55. 2026-09-04 12:27 UTCVendor advisory
  56. 2026-09-04 05:07 UTCEPSS rescore
  57. 2026-09-04 00:53 UTCVendor advisory
  58. 2026-09-03 13:18 UTCEG score recompute
  59. 2026-09-03 05:00 UTCEG score recompute
  60. 2026-09-02 20:22 UTCEG score recompute
  61. 2026-09-02 19:28 UTCEG score recompute
  62. 2026-09-02 14:12 UTCEPSS rescore
  63. 2026-09-01 21:27 UTCEG score recompute
  64. 2026-09-01 20:23 UTCEG score recompute
  65. 2026-09-01 20:22 UTCMITRE cvelistV5first tracked

Related CVEs(same product + same vendor + same CWE)

Same vendor

1 shown

redhat:RHSA-2026:63151

Frequently asked(5)

What is CVE-2026-84361?
CVE-2026-84361 is a high vulnerability published on September 1, 2026. Composer is a dependency Manager for the PHP language. From 1.0 until 2.2.30 and 2.10.3, a malicious dependency package from a custom Composer repository or an untrusted composer.lock file could set source.type to perforce and source.url to an rsh: or jsh: P4PORT value. When the Perforce p4 client…
When was CVE-2026-84361 disclosed?
CVE-2026-84361 was first published in the National Vulnerability Database on September 1, 2026, with the most recent update 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-2026-84361 actively exploited?
CVE-2026-84361 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 56.6% of all scored CVEs.
What is the CVSS score of CVE-2026-84361?
CVE-2026-84361 has a CVSS v3 base score of 7.7 (NVD).
How do I remediate CVE-2026-84361?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-84361, 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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