Vulnerability-Lookup

CERTFR-2026-AVI-0599

Vulnerability from certfr_avis - Published: 2026-05-15 - Updated: 2026-05-15

Une vulnérabilité a été découverte dans Microsoft Exchange Server. Elle permet à un attaquant de provoquer une injection de code indirecte à distance (XSS) et un contournement de la politique de sécurité.

Microsoft indique que la vulnérabilité CVE-2026-42897 est activement exploitée.

Solutions

Se référer au bulletin de sécurité de l'éditeur pour l'obtention des correctifs (cf. section Documentation).

Impacted products

Vendor	Product	Description
Microsoft	N/A	Microsoft Exchange Server 2019 Cumulative Update 15
Microsoft	N/A	Microsoft Exchange Server 2016 Cumulative Update 23
Microsoft	N/A	Microsoft Exchange Server Subscription Edition RTM
Microsoft	N/A	Microsoft Exchange Server 2019 Cumulative Update 14

References

Title

Publication Time

Tags

Bulletin de sécurité Microsoft CVE-2026-42897

2026-05-14

vendor-advisory

Show details on source website

JSON

To clipboard

{
  "$ref": "https://www.cert.ssi.gouv.fr/openapi.json",
  "affected_systems": [
    {
      "description": "Microsoft Exchange Server 2019 Cumulative Update 15",
      "product": {
        "name": "N/A",
        "vendor": {
          "name": "Microsoft",
          "scada": false
        }
      }
    },
    {
      "description": "Microsoft Exchange Server 2016 Cumulative Update 23",
      "product": {
        "name": "N/A",
        "vendor": {
          "name": "Microsoft",
          "scada": false
        }
      }
    },
    {
      "description": "Microsoft Exchange Server Subscription Edition RTM",
      "product": {
        "name": "N/A",
        "vendor": {
          "name": "Microsoft",
          "scada": false
        }
      }
    },
    {
      "description": "Microsoft Exchange Server 2019 Cumulative Update 14",
      "product": {
        "name": "N/A",
        "vendor": {
          "name": "Microsoft",
          "scada": false
        }
      }
    }
  ],
  "affected_systems_content": "",
  "content": "## Solutions\n\nSe r\u00e9f\u00e9rer au bulletin de s\u00e9curit\u00e9 de l\u0027\u00e9diteur pour l\u0027obtention des correctifs (cf. section Documentation).",
  "cves": [
    {
      "name": "CVE-2026-42897",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-42897"
    }
  ],
  "initial_release_date": "2026-05-15T00:00:00",
  "last_revision_date": "2026-05-15T00:00:00",
  "links": [],
  "reference": "CERTFR-2026-AVI-0599",
  "revisions": [
    {
      "description": "Version initiale",
      "revision_date": "2026-05-15T00:00:00.000000"
    }
  ],
  "risks": [
    {
      "description": "Injection de code indirecte \u00e0 distance (XSS)"
    },
    {
      "description": "Contournement de la politique de s\u00e9curit\u00e9"
    }
  ],
  "summary": "Une vuln\u00e9rabilit\u00e9 a \u00e9t\u00e9 d\u00e9couverte dans Microsoft Exchange Server. Elle permet \u00e0 un attaquant de provoquer une injection de code indirecte \u00e0 distance (XSS) et un contournement de la politique de s\u00e9curit\u00e9.\n\nMicrosoft indique que la vuln\u00e9rabilit\u00e9 CVE-2026-42897 est activement exploit\u00e9e.",
  "title": "Vuln\u00e9rabilit\u00e9 dans Microsoft Exchange Server",
  "vendor_advisories": [
    {
      "published_at": "2026-05-14",
      "title": "Bulletin de s\u00e9curit\u00e9 Microsoft CVE-2026-42897",
      "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42897"
    }
  ]
}

CVE-2026-42897 (GCVE-0-2026-42897)

Vulnerability from cvelistv5 – Published: 2026-05-14 17:00 – Updated: 2026-05-26 16:56

Title

Microsoft Exchange Server Spoofing Vulnerability

Summary

Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Exchange Server allows an unauthorized attacker to perform spoofing over a network.

Severity

8.1 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N/E:F/RL:O/RC:C

CWE

CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Assigner

microsoft

References

1 reference

URL	Tags
https://msrc.microsoft.com/update-guide/vulnerabi…	vendor-advisorypatch

Impacted products

4 products

Vendor	Product	Version
Microsoft	Microsoft Exchange Server 2016 Cumulative Update 23	Affected: -
Microsoft	Microsoft Exchange Server 2019 Cumulative Update 14	Affected: -
Microsoft	Microsoft Exchange Server 2019 Cumulative Update 15	Affected: -
Microsoft	Microsoft Exchange Server Subscription Edition RTM	Affected: -

Date Public

2026-05-14 14:00

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

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