CVE-2026-55418

HIGHPre-NVD 8.68.6
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to the CVSS score beside it.

This high-severity CVE scores 8.6 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.5% (39th percentile of EPSS-scored CVEs). No GitHub Security Advisory CVSS is on record for this CVE.

Triggered by: Headline CVSS from a secondary CVSS source
Sources: EPSS, a secondary CVSS source
8.6EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.5%CVSS: 8.6Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

FastGPT is an open source AI knowledge base platform. Prior to v4.15.0-beta5, two FastGPT file handlers authorize an unrelated resource and then sign or read an S3 object using a key taken directly from the request, without checking that the key belongs to the caller's team. Because S3 object keys are global within the bucket and carry the tenant id only as a path segment, an attacker can supply another team's key and obtain its file contents through the chat-file presign endpoint or dataset preview endpoint. This issue is fixed in version v4.15.0-beta5.

CVSS v3
8.6
EG Score
8.6HIGHmedium confidence
EG Risk
54
EG Risk 54/100

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 (value × EchelonGraph’s weight)
Severity86% × 45%
The EG Score, 8.6 of 10.
Exploitation0.5% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability100% × 15%
CISA's SSVC Automatable value: yes (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Attend at high (mission-essential systems).
Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
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
0.5%
EPSS %ILE
39th
KEV
Not listed

SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; 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 (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; 60 days if it is not.

In CISA KEV no (CISA's KEV catalog) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

July 7, 2026

Last Modified

July 9, 2026

Advisory Details (4)

Auto-updated Jul 7, 2026
Patch available. Sources: github_release, github, github_commit, github_pr.
GitHub advisoryMentions a patch (unverified)

S3 presign/read handlers do not bind the object key to the caller's team (cross-team file disclosure) · Advisory · labring/FastGPT · GitHub

https://github.com/labring/FastGPT/security/advisories/GHSA-6rxv-p43w-mmx5
GitHub release Patch Available

v4.15.0-beta5

Patch available: labring/FastGPT v4.15.0-beta5 (pre-release)

https://github.com/labring/FastGPT/releases/tag/v4.15.0-beta5
GitHub pull request Patch Available

fix: bind S3 object keys to authorized resources

Patch available: labring/FastGPT v4.15.0-beta5 (PR #7104 merged 2026-06-12)

https://github.com/labring/FastGPT/pull/7104
GitHub commit Patch Available

commit decb6d2fb141 (labring/FastGPT)

Patch available: labring/FastGPT v4.15.0-beta5 (contains commit decb6d2fb141)

https://github.com/labring/FastGPT/commit/decb6d2fb1417fb9e2bca145d2dcc9cbcf06396c

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 10× in last 7d / 32× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. 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. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

Showing the most recent 100 of 139 refreshes on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 39 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-11 19:39 UTCEG score recompute
  2. 2026-10-11 16:54 UTCEG score recompute
  3. 2026-10-11 14:17 UTCEG score recompute
  4. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  5. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  6. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  7. 2026-10-08 17:12 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  8. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  9. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  10. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  11. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  12. 2026-10-03 14:26 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  13. 2026-10-02 17:56 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  14. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  15. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  16. 2026-09-29 15:22 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  17. 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  18. 2026-09-28 13:35 UTCEG score recompute
  19. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  20. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  21. 2026-09-24 14:04 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  22. 2026-09-23 17:54 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  23. 2026-09-23 06:16 UTCEG score recompute
  24. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  25. 2026-09-18 05:48 UTCEG score recompute
Show 75 more
  1. 2026-09-17 19:31 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  2. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  3. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  4. 2026-09-15 03:11 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  5. 2026-09-13 23:52 UTCEG score recompute
  6. 2026-09-13 16:47 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  7. 2026-09-12 16:10 UTCEG score recompute
  8. 2026-09-12 03:41 UTCEG score recompute
  9. 2026-09-11 14:53 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  10. 2026-09-10 09:35 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  11. 2026-09-08 22:01 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  12. 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  13. 2026-09-06 14:07 UTCEG score recompute
  14. 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  15. 2026-09-05 22:53 UTCEG score recompute
  16. 2026-09-04 05:06 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  17. 2026-09-02 14:12 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  18. 2026-09-01 13:54 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  19. 2026-09-01 04:40 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  20. 2026-08-30 20:11 UTCEG score recompute
  21. 2026-08-30 19:17 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  22. 2026-08-30 07:41 UTCEG score recompute
  23. 2026-08-30 01:22 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  24. 2026-08-28 21:41 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  25. 2026-08-27 21:54 UTCEG score recompute
  26. 2026-08-27 14:25 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  27. 2026-08-27 01:52 UTCEG score recompute
  28. 2026-08-26 14:46 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  29. 2026-08-26 12:57 UTCEG score recompute
  30. 2026-08-25 13:49 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  31. 2026-08-24 22:17 UTCEG score recompute
  32. 2026-08-24 09:48 UTCEG score recompute
  33. 2026-08-23 06:40 UTCEG score recompute
  34. 2026-08-23 00:19 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  35. 2026-08-22 05:40 UTCEG score recompute
  36. 2026-08-21 23:49 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  37. 2026-08-21 04:10 UTCEG score recompute
  38. 2026-08-20 22:55 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  39. 2026-08-20 02:10 UTCEG score recompute
  40. 2026-08-19 17:04 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  41. 2026-08-18 20:47 UTCEG score recompute
  42. 2026-08-18 13:48 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  43. 2026-08-17 15:01 UTCEG score recompute
  44. 2026-08-17 13:47 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  45. 2026-08-17 02:32 UTCEG score recompute
  46. 2026-08-16 14:56 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  47. 2026-08-16 14:03 UTCEG score recompute
  48. 2026-08-16 02:14 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  49. 2026-08-15 13:05 UTCEG score recompute
  50. 2026-08-15 01:30 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  51. 2026-08-13 23:38 UTCEG score recompute
  52. 2026-08-13 22:00 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  53. 2026-08-12 22:38 UTCEG score recompute
  54. 2026-08-12 13:51 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  55. 2026-08-11 21:40 UTCEG score recompute
  56. 2026-08-11 09:11 UTCEG score recompute
  57. 2026-08-11 00:00 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  58. 2026-08-09 19:45 UTCEG score recompute
  59. 2026-08-09 13:46 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  60. 2026-08-08 18:48 UTCEG score recompute
  61. 2026-08-08 16:37 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  62. 2026-08-07 17:51 UTCEG score recompute
  63. 2026-08-06 16:53 UTCEG score recompute
  64. 2026-08-06 13:47 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  65. 2026-08-06 04:24 UTCEG score recompute
  66. 2026-08-05 19:17 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  67. 2026-08-05 02:51 UTCEG score recompute
  68. 2026-08-04 15:10 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  69. 2026-08-04 14:22 UTCEG score recompute
  70. 2026-08-04 10:39 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  71. 2026-08-03 13:24 UTCEG score recompute
  72. 2026-08-03 10:36 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  73. 2026-08-02 12:27 UTCEG score recompute
  74. 2026-08-02 02:27 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  75. 2026-08-01 11:29 UTCEG score recompute

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-55418?
CVE-2026-55418 is a high-severity vulnerability; its CVE record was published on July 7, 2026. FastGPT is an open source AI knowledge base platform. Prior to v4.15.0-beta5, two FastGPT file handlers authorize an unrelated resource and then sign or read an S3 object using a key taken directly from the request, without checking that the key belongs to the caller's team. Because S3 object keys…
When was the CVE record for CVE-2026-55418 published?
The CVE record for CVE-2026-55418 was published on July 7, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of July 9, 2026; the record at its source may have been updated since.
Is CVE-2026-55418 actively exploited?
CVE-2026-55418 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.5% probability of exploitation in the next 30 days (39th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-55418?
CVE-2026-55418 has a CVSS base score of 8.6 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-55418?
A fix for CVE-2026-55418 is available: update to the fixed version the vendor names in its advisory.

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