CVE-2026-91857

MEDIUMPre-NVD 5.35.3
EchelonGraph scoreMEDIUM confidence

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

This medium-severity CVE scores 5.3 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.2% (11th 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

Also known asEUVD-2026-78348 (ENISA EUVD) · GHSA-6wvj-vm6h-rf24 (GitHub Security Advisories)Source: ENISA EUVD

5.3EG
EchelonGraph verdictMonitorRemediate within your standard update timelines (the SSVC decision on this page).
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.2%CVSS: 5.3Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

Affected versions of MISP expose several state-changing controller actions without restricting them to POST.

The affected actions are:

  • EventReportsController::purgeUnusedPictures()
  • NoticelistsController::enableNoticelist()
  • ServersController::removeOrphanedCorrelations()
  • WorkflowsController::rebuildRedis()

The patch adds allowMethod(['post']) to each action, preventing them from being triggered through ordinary GET requests.

For purgeUnusedPictures(), the corresponding UI previously used $.get(). The fix converts that request to POST and supplies X-CSRF-Token, while the controller enables header-only CSRF validation for that AJAX action.

Because GET requests can be induced cross-origin through links, images, redirects, or navigation, accepting GET for these state-changing operations can let an attacker trigger them using the authenticated victim's session.

Version affected: ≤2.5.45

CVSS v3
5.3
EG Score
5.3MEDIUMmedium confidence
EG Risk
24
EG Risk 24/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity53% × 45%
Impact severity (EG Severity): CVSS 5.3 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.2% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at every mission impact level.
Exploitation none (CISA Vulnrichment) · Automatable no (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.
EPSS PROB
0.2%
EPSS %ILE
11th
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (5.3): severity, escalated by confirmed exploitation. This CVE's 5.3 is its impact severity (EG Severity), not escalated.

EG Severity
5.3 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.a secondary CVSS source · CVSS v3.0 or v3.1
EG Likelihood
0.2% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-24). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track at medium mission impactTrack at every mission impact level.CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at every mission impact level.

A fix is available. Apply it within your standard update timelines.

Exploitation none (CISA Vulnrichment) · Automatable no (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)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (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

September 15, 2026

Last Modified

September 16, 2026

Advisory Details (1)

Auto-updated Sep 15, 2026
Patch available. Sources: github_commit.
GitHub commit Patch Available

commit b4a5486b5 (MISP/MISP)

Patch available: MISP/MISP v2.5.46 (contains commit b4a5486b5)

https://github.com/MISP/MISP/commit/b4a5486b5

Vendor Advisories for CVE-2026-91857(1)

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

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 8× in last 7d / 53× 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 99 of 112 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. 1 repeat row among the latest 100 is merged into the row it repeats. The 13 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-01 16:36 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  2. 2026-10-31 16:33 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  3. 2026-10-30 16:35 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  4. 2026-10-29 22:25 UTCOSV refresh
  5. 2026-10-29 16:34 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  6. 2026-10-28 16:33 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  7. 2026-10-27 16:33 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  8. 2026-10-26 16:33 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  9. 2026-10-25 16:34 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  10. 2026-10-25 13:50 UTCEG score recompute
  11. 2026-10-24 16:34 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  12. 2026-10-23 16:32 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  13. 2026-10-22 16:35 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  14. 2026-10-22 12:30 UTCEG score recompute
  15. 2026-10-22 12:30 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  16. 2026-10-21 16:34 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  17. 2026-10-20 16:34 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  18. 2026-10-19 16:33 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  19. 2026-10-18 16:33 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  20. 2026-10-18 03:00 UTCEG score recompute
  21. 2026-10-17 16:35 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  22. 2026-10-16 16:45 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  23. 2026-10-15 16:33 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  24. 2026-10-14 16:34 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  25. 2026-10-13 16:35 UTCEPSS rescoreEPSS 0.2% · 10th percentile
Show 74 more
  1. 2026-10-12 16:35 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  2. 2026-10-12 14:45 UTCEG score recompute
  3. 2026-10-11 19:35 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  4. 2026-10-11 19:13 UTCEG score recompute
  5. 2026-10-11 16:29 UTCEG score recompute
  6. 2026-10-11 13:50 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  7. 2026-10-11 13:44 UTCEG score recompute
  8. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  9. 2026-10-10 19:38 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  10. 2026-10-09 20:53 UTCEG score recompute
  11. 2026-10-09 20:53 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  12. 2026-10-09 20:08 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  13. 2026-10-08 22:42 UTCEG score recompute
  14. 2026-10-08 22:42 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  15. 2026-10-08 17:14 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  16. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  17. 2026-10-07 22:21 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  18. 2026-10-06 23:45 UTCEG score recompute
  19. 2026-10-06 23:45 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  20. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  21. 2026-10-06 01:36 UTCEG score recompute
  22. 2026-10-06 01:36 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  23. 2026-10-05 17:44 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  24. 2026-10-05 03:12 UTCEG score recompute
  25. 2026-10-05 03:12 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  26. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  27. 2026-10-04 04:37 UTCEG score recompute
  28. 2026-10-04 04:37 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  29. 2026-10-03 06:28 UTCEG score recompute
  30. 2026-10-03 06:28 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  31. 2026-10-02 08:18 UTCEG score recompute
  32. 2026-10-02 08:18 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  33. 2026-10-01 19:51 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  34. 2026-10-01 10:08 UTCEG score recompute
  35. 2026-10-01 10:08 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  36. 2026-09-30 15:04 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  37. 2026-09-30 11:59 UTCEG score recompute
  38. 2026-09-30 11:59 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  39. 2026-09-29 13:49 UTCEG score recompute
  40. 2026-09-29 13:49 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  41. 2026-09-28 15:39 UTCEG score recompute
  42. 2026-09-28 15:39 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  43. 2026-09-28 13:52 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  44. 2026-09-27 17:22 UTCEG score recompute
  45. 2026-09-27 17:22 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  46. 2026-09-27 13:49 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  47. 2026-09-26 19:08 UTCEG score recompute
  48. 2026-09-26 19:08 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  49. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  50. 2026-09-25 20:53 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  51. 2026-09-24 21:41 UTCEG score recompute
  52. 2026-09-24 21:41 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  53. 2026-09-24 14:04 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  54. 2026-09-23 23:26 UTCEG score recompute
  55. 2026-09-23 23:26 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  56. 2026-09-23 17:54 UTCEPSS rescoreEPSS 0.2% · 6th percentile
  57. 2026-09-23 01:16 UTCEG score recompute
  58. 2026-09-23 01:16 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  59. 2026-09-22 16:01 UTCEPSS rescoreEPSS 0.2% · 6th percentile
  60. 2026-09-22 03:06 UTCEG score recompute
  61. 2026-09-22 03:06 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  62. 2026-09-21 21:09 UTCEPSS rescoreEPSS 0.2% · 6th percentile
  63. 2026-09-21 04:55 UTCEG score recompute
  64. 2026-09-21 04:55 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  65. 2026-09-20 20:16 UTCEPSS rescoreEPSS 0.2% · 6th percentile
  66. 2026-09-20 06:28 UTCEG score recompute
  67. 2026-09-20 06:27 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  68. 2026-09-19 08:13 UTCEG score recompute
  69. 2026-09-19 08:13 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  70. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.2% · 6th percentile
  71. 2026-09-18 10:04 UTCEG score recompute
  72. 2026-09-18 10:04 UTCGHSA enrichmentGHSA-6wvj-vm6h-rf24
  73. 2026-09-17 19:32 UTCEPSS rescoreEPSS 0.2% · 6th percentile
  74. 2026-09-17 11:54 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-91857?
CVE-2026-91857 is a medium-severity vulnerability; its CVE record was published on September 15, 2026. Affected versions of MISP expose several state-changing controller actions without restricting them to POST. The affected actions are: EventReportsController::purgeUnusedPictures() NoticelistsController::enableNoticelist() ServersController::removeOrphanedCorrelations()…
When was the CVE record for CVE-2026-91857 published?
The CVE record for CVE-2026-91857 was published on September 15, 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 September 16, 2026; the record at its source may have been updated since.
Is CVE-2026-91857 actively exploited?
CVE-2026-91857 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.2% probability of exploitation in the next 30 days (11th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-91857?
CVE-2026-91857 has a CVSS base score of 5.3 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-91857?
A fix for CVE-2026-91857 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-91857 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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