FKIE_CVE-2025-8277

Vulnerability from fkie_nvd - Published: 2025-09-09 12:15 - Updated: 2026-10-18 21:10
Severity
3.1 (Low) - CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L
Summary
A flaw was found in libssh's handling of key exchange (KEX) processes when a client repeatedly sends incorrect KEX guesses. The library fails to free memory during these rekey operations, which can gradually exhaust system memory. This issue can lead to crashes on the client side, particularly when using libgcrypt, which impacts application stability and availability.
References
secalert@redhat.comhttps://access.redhat.com/errata/RHSA-2026:18683
secalert@redhat.comhttps://access.redhat.com/security/cve/CVE-2025-8277
secalert@redhat.comhttps://bugzilla.redhat.com/show_bug.cgi?id=2383888
secalert@redhat.comhttps://www.libssh.org/security/advisories/CVE-2025-8277.txt
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "collectionURL": "https://www.libssh.org",
          "defaultStatus": "unaffected",
          "packageName": "libssh",
          "versions": [
            {
              "lessThan": "0.11.3",
              "status": "affected",
              "version": "0.6.0",
              "versionType": "semver"
            }
          ]
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/a:redhat:enterprise_linux:9::appstream",
            "cpe:/o:redhat:enterprise_linux:9::baseos"
          ],
          "defaultStatus": "affected",
          "packageName": "libssh",
          "product": "Red Hat Enterprise Linux 9",
          "vendor": "Red Hat",
          "versions": [
            {
              "lessThan": "*",
              "status": "unaffected",
              "version": "0:0.10.4-18.el9",
              "versionType": "rpm"
            }
          ]
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/a:redhat:enterprise_linux:9::appstream",
            "cpe:/o:redhat:enterprise_linux:9::baseos"
          ],
          "defaultStatus": "affected",
          "packageName": "libssh",
          "product": "Red Hat Enterprise Linux 9",
          "vendor": "Red Hat",
          "versions": [
            {
              "lessThan": "*",
              "status": "unaffected",
              "version": "0:0.10.4-18.el9",
              "versionType": "rpm"
            }
          ]
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:10"
          ],
          "defaultStatus": "affected",
          "packageName": "libssh",
          "product": "Red Hat Enterprise Linux 10",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:6"
          ],
          "defaultStatus": "unknown",
          "packageName": "libssh2",
          "product": "Red Hat Enterprise Linux 6",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:7"
          ],
          "defaultStatus": "affected",
          "packageName": "libssh2",
          "product": "Red Hat Enterprise Linux 7",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:8"
          ],
          "defaultStatus": "affected",
          "packageName": "libssh",
          "product": "Red Hat Enterprise Linux 8",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/a:redhat:openshift:4"
          ],
          "defaultStatus": "affected",
          "packageName": "openshift/ose-rhel-coreos-8",
          "product": "Red Hat OpenShift Container Platform 4",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/a:redhat:openshift:4"
          ],
          "defaultStatus": "affected",
          "packageName": "openshift/ose-rhel-coreos-9",
          "product": "Red Hat OpenShift Container Platform 4",
          "vendor": "Red Hat"
        }
      ],
      "source": "secalert@redhat.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A flaw was found in libssh\u0027s handling of key exchange (KEX) processes when a client repeatedly sends incorrect KEX guesses. The library fails to free memory during these rekey operations, which can gradually exhaust system memory. This issue can lead to crashes on the client side, particularly when using libgcrypt, which impacts application stability and availability."
    },
    {
      "lang": "es",
      "value": "Se encontr\u00f3 una falla en el manejo de libssh de los procesos de intercambio de claves (KEX) cuando un cliente env\u00eda repetidamente suposiciones KEX incorrectas. La biblioteca no libera memoria durante estas operaciones de renegociaci\u00f3n de clave, lo que puede agotar gradualmente la memoria del sistema. Este problema puede provocar fallos en el lado del cliente, particularmente al usar libgcrypt, lo que afecta la estabilidad y disponibilidad de la aplicaci\u00f3n."
    }
  ],
  "id": "CVE-2025-8277",
  "lastModified": "2026-10-18T21:10:00.120",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "LOW",
          "baseScore": 3.1,
          "baseSeverity": "LOW",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L",
          "version": "3.1"
        },
        "exploitabilityScore": 1.6,
        "impactScore": 1.4,
        "source": "secalert@redhat.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2025-8277",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2025-09-09T19:28:17.013547Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2025-09-09T12:15:30.677",
  "references": [
    {
      "source": "secalert@redhat.com",
      "url": "https://access.redhat.com/errata/RHSA-2026:18683"
    },
    {
      "source": "secalert@redhat.com",
      "url": "https://access.redhat.com/security/cve/CVE-2025-8277"
    },
    {
      "source": "secalert@redhat.com",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2383888"
    },
    {
      "source": "secalert@redhat.com",
      "url": "https://www.libssh.org/security/advisories/CVE-2025-8277.txt"
    }
  ],
  "sourceIdentifier": "secalert@redhat.com",
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-401"
        }
      ],
      "source": "secalert@redhat.com",
      "type": "Secondary"
    }
  ]
}



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