GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

CVE-2026-48851 (GCVE-0-2026-48851)

Vulnerability from cvelistv5 – Published: 2026-05-25 20:16 – Updated: 2026-05-26 12:40
VLAI
Summary
PuTTY 0.77 before 0.84 uses a copy of the PuTTY icon as a trust indication for TELNET data but the trust status is not cleared between proxy authentication and the main session.
Severity
3.1 (Low)
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-26 12:40 UTC
CWE
  • CWE-451 - User Interface (UI) Misrepresentation of Critical Information
Assigner
References
Impacted products
Vendor Product Version CPE status
PuTTY PuTTY Affected: 0.77 , < 0.84 (custom)
    cpe:2.3:a:putty:putty:*:*:*:*:*:*:*:*
Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-48851",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-05-26T12:40:42.460737Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-05-26T12:40:49.268Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "PuTTY",
          "vendor": "PuTTY",
          "versions": [
            {
              "lessThan": "0.84",
              "status": "affected",
              "version": "0.77",
              "versionType": "custom"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:putty:putty:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "0.84",
                  "versionStartIncluding": "0.77",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "PuTTY 0.77 before 0.84 uses a copy of the PuTTY icon as a trust indication for TELNET data but the trust status is not cleared between proxy authentication and the main session."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 3.1,
            "baseSeverity": "LOW",
            "confidentialityImpact": "NONE",
            "integrityImpact": "LOW",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-451",
              "description": "CWE-451 User Interface (UI) Misrepresentation of Critical Information",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-25T20:16:31.485Z",
        "orgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
        "shortName": "mitre"
      },
      "references": [
        {
          "url": "https://lists.tartarus.org/pipermail/putty-announce/2026/000042.html"
        },
        {
          "url": "https://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/telnet-trust-sigil.html"
        }
      ],
      "x_generator": {
        "engine": "CVE-Request-form 0.0.1"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
    "assignerShortName": "mitre",
    "cveId": "CVE-2026-48851",
    "datePublished": "2026-05-25T20:16:31.485Z",
    "dateReserved": "2026-05-25T20:16:30.998Z",
    "dateUpdated": "2026-05-26T12:40:49.268Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-48851",
      "date": "2026-09-16",
      "epss": "0.00224",
      "percentile": "0.13116"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-48851\",\"sourceIdentifier\":\"cve@mitre.org\",\"published\":\"2026-05-25T21:16:35.400\",\"lastModified\":\"2026-07-24T10:10:00.197\",\"vulnStatus\":\"Analyzed\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"PuTTY 0.77 before 0.84 uses a copy of the PuTTY icon as a trust indication for TELNET data but the trust status is not cleared between proxy authentication and the main session.\"},{\"lang\":\"es\",\"value\":\"PuTTY 0.77 anterior a 0.84 utiliza una copia del icono de PuTTY como una indicaci\u00f3n de confianza para datos TELNET pero el estado de confianza no se borra entre la autenticaci\u00f3n de proxy y la sesi\u00f3n principal.\"}],\"affected\":[{\"source\":\"cve@mitre.org\",\"affectedData\":[{\"vendor\":\"PuTTY\",\"product\":\"PuTTY\",\"defaultStatus\":\"unaffected\",\"versions\":[{\"version\":\"0.77\",\"lessThan\":\"0.84\",\"versionType\":\"custom\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"cve@mitre.org\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N\",\"baseScore\":3.1,\"baseSeverity\":\"LOW\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"HIGH\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"REQUIRED\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"LOW\",\"availabilityImpact\":\"NONE\"},\"exploitabilityScore\":1.6,\"impactScore\":1.4}],\"ssvcV203\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"ssvcData\":{\"timestamp\":\"2026-05-26T12:40:42.460737Z\",\"id\":\"CVE-2026-48851\",\"options\":[{\"exploitation\":\"none\"},{\"automatable\":\"no\"},{\"technicalImpact\":\"partial\"}],\"role\":\"CISA Coordinator\",\"version\":\"2.0.3\"}}]},\"weaknesses\":[{\"source\":\"cve@mitre.org\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-451\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:putty:putty:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"0.77\",\"versionEndExcluding\":\"0.84\",\"matchCriteriaId\":\"FF65EC81-FDC8-42A3-9608-A005EAA76A21\"}]}]}],\"references\":[{\"url\":\"https://lists.tartarus.org/pipermail/putty-announce/2026/000042.html\",\"source\":\"cve@mitre.org\",\"tags\":[\"Release Notes\"]},{\"url\":\"https://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/telnet-trust-sigil.html\",\"source\":\"cve@mitre.org\",\"tags\":[\"Patch\",\"Vendor Advisory\"]}]}}",
    "redhat_vex": {
      "current_release_date": "2026-06-28T07:43:02+00:00",
      "cve": "CVE-2026-48851",
      "id": "CVE-2026-48851",
      "initial_release_date": "2026-05-25T20:16:31.485000+00:00",
      "product_status:known_not_affected": "1",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "PuTTY: TELNET session data is marked with trust sigils after authenticating to a proxy",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-48851.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "low",
      "current_release_date": "2026-05-27T12:57:12Z",
      "cve": "CVE-2026-48851",
      "id": "CVE-2026-48851",
      "initial_release_date": "2026-05-27T12:57:12Z",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-48851",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-48851.json",
      "version": "2"
    },
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-48851\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-05-26T12:40:42.460737Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-05-26T12:40:45.994Z\"}}], \"cna\": {\"metrics\": [{\"format\": \"CVSS\", \"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 3.1, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"LOW\", \"vectorString\": \"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N\", \"integrityImpact\": \"LOW\", \"userInteraction\": \"REQUIRED\", \"attackComplexity\": \"HIGH\", \"availabilityImpact\": \"NONE\", \"privilegesRequired\": \"NONE\", \"confidentialityImpact\": \"NONE\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"GENERAL\"}]}], \"affected\": [{\"vendor\": \"PuTTY\", \"product\": \"PuTTY\", \"versions\": [{\"status\": \"affected\", \"version\": \"0.77\", \"lessThan\": \"0.84\", \"versionType\": \"custom\"}], \"defaultStatus\": \"unaffected\"}], \"references\": [{\"url\": \"https://lists.tartarus.org/pipermail/putty-announce/2026/000042.html\"}, {\"url\": \"https://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/telnet-trust-sigil.html\"}], \"x_generator\": {\"engine\": \"CVE-Request-form 0.0.1\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"PuTTY 0.77 before 0.84 uses a copy of the PuTTY icon as a trust indication for TELNET data but the trust status is not cleared between proxy authentication and the main session.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-451\", \"description\": \"CWE-451 User Interface (UI) Misrepresentation of Critical Information\"}]}], \"cpeApplicability\": [{\"nodes\": [{\"negate\": false, \"cpeMatch\": [{\"criteria\": \"cpe:2.3:a:putty:putty:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"0.84\", \"versionStartIncluding\": \"0.77\"}], \"operator\": \"OR\"}]}], \"providerMetadata\": {\"orgId\": \"8254265b-2729-46b6-b9e3-3dfca2d5bfca\", \"shortName\": \"mitre\", \"dateUpdated\": \"2026-05-25T20:16:31.485Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-48851\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-05-26T12:40:49.268Z\", \"dateReserved\": \"2026-05-25T20:16:30.998Z\", \"assignerOrgId\": \"8254265b-2729-46b6-b9e3-3dfca2d5bfca\", \"datePublished\": \"2026-05-25T20:16:31.485Z\", \"assignerShortName\": \"mitre\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.