CVE-2026-44195 (GCVE-0-2026-44195)

Vulnerability from cvelistv5 – Published: 2026-05-13 21:52 – Updated: 2026-05-14 13:46
VLAI?
Title
OPNsense: Authentication lockout bypass
Summary
OPNsense is a FreeBSD based firewall and routing platform. Prior to 26.1.7, a logic flaw in the OPNsense lockout_handler allows an unauthenticated attacker to continuously reset the authentication failure counter for their IP address. By interjecting a crafted username containing a success keyword ("Accepted" or "Successful login") between normal brute-force attempts, an attacker can prevent the failure counter from ever reaching the lockout threshold. This vulnerability is fixed in 26.1.7.
Severity ?
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
CWE
  • CWE-307 - Improper Restriction of Excessive Authentication Attempts
Assigner
References
Impacted products
Vendor Product Version
opnsense core Affected: < 26.1.7
Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-44195",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-05-14T13:46:23.604362Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-05-14T13:46:30.721Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://gist.github.com/sopex/b9786e72e2a5d9b1bbd81ed8477c351b"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "core",
          "vendor": "opnsense",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 26.1.7"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "OPNsense is a FreeBSD based firewall and routing platform. Prior to 26.1.7, a logic flaw in the OPNsense lockout_handler allows an unauthenticated attacker to continuously reset the authentication failure counter for their IP address. By interjecting a crafted username containing a success keyword (\"Accepted\" or \"Successful login\") between normal brute-force attempts, an attacker can prevent the failure counter from ever reaching the lockout threshold. This vulnerability is fixed in 26.1.7."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 5.3,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "LOW",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-307",
              "description": "CWE-307: Improper Restriction of Excessive Authentication Attempts",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-13T21:52:42.373Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/opnsense/core/security/advisories/GHSA-h3vx-4q27-rc42",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/opnsense/core/security/advisories/GHSA-h3vx-4q27-rc42"
        }
      ],
      "source": {
        "advisory": "GHSA-h3vx-4q27-rc42",
        "discovery": "UNKNOWN"
      },
      "title": "OPNsense: Authentication lockout bypass"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-44195",
    "datePublished": "2026-05-13T21:52:42.373Z",
    "dateReserved": "2026-05-05T15:13:47.570Z",
    "dateUpdated": "2026-05-14T13:46:30.721Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-44195",
      "date": "2026-05-16",
      "epss": "0.00082",
      "percentile": "0.2392"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-44195\",\"sourceIdentifier\":\"security-advisories@github.com\",\"published\":\"2026-05-13T22:16:43.820\",\"lastModified\":\"2026-05-15T16:06:30.720\",\"vulnStatus\":\"Analyzed\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"OPNsense is a FreeBSD based firewall and routing platform. Prior to 26.1.7, a logic flaw in the OPNsense lockout_handler allows an unauthenticated attacker to continuously reset the authentication failure counter for their IP address. By interjecting a crafted username containing a success keyword (\\\"Accepted\\\" or \\\"Successful login\\\") between normal brute-force attempts, an attacker can prevent the failure counter from ever reaching the lockout threshold. This vulnerability is fixed in 26.1.7.\"}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N\",\"baseScore\":5.3,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"LOW\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"NONE\"},\"exploitabilityScore\":3.9,\"impactScore\":1.4},{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N\",\"baseScore\":6.5,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"LOW\",\"integrityImpact\":\"LOW\",\"availabilityImpact\":\"NONE\"},\"exploitabilityScore\":3.9,\"impactScore\":2.5}]},\"weaknesses\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-307\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:opnsense:opnsense:*:*:*:*:*:*:*:*\",\"versionEndExcluding\":\"26.1.7\",\"matchCriteriaId\":\"56B95741-5F9C-4FA1-A607-456BB4C29944\"}]}]}],\"references\":[{\"url\":\"https://github.com/opnsense/core/security/advisories/GHSA-h3vx-4q27-rc42\",\"source\":\"security-advisories@github.com\",\"tags\":[\"Exploit\",\"Mitigation\",\"Vendor Advisory\"]},{\"url\":\"https://gist.github.com/sopex/b9786e72e2a5d9b1bbd81ed8477c351b\",\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"tags\":[\"Exploit\"]}]}}",
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-44195\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"poc\"}, {\"Automatable\": \"yes\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-05-14T13:46:23.604362Z\"}}}], \"references\": [{\"url\": \"https://gist.github.com/sopex/b9786e72e2a5d9b1bbd81ed8477c351b\", \"tags\": [\"exploit\"]}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-05-14T13:46:18.566Z\"}}], \"cna\": {\"title\": \"OPNsense: Authentication lockout bypass\", \"source\": {\"advisory\": \"GHSA-h3vx-4q27-rc42\", \"discovery\": \"UNKNOWN\"}, \"metrics\": [{\"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 5.3, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"MEDIUM\", \"vectorString\": \"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N\", \"integrityImpact\": \"NONE\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"NONE\", \"privilegesRequired\": \"NONE\", \"confidentialityImpact\": \"LOW\"}}], \"affected\": [{\"vendor\": \"opnsense\", \"product\": \"core\", \"versions\": [{\"status\": \"affected\", \"version\": \"\u003c 26.1.7\"}]}], \"references\": [{\"url\": \"https://github.com/opnsense/core/security/advisories/GHSA-h3vx-4q27-rc42\", \"name\": \"https://github.com/opnsense/core/security/advisories/GHSA-h3vx-4q27-rc42\", \"tags\": [\"x_refsource_CONFIRM\"]}], \"descriptions\": [{\"lang\": \"en\", \"value\": \"OPNsense is a FreeBSD based firewall and routing platform. Prior to 26.1.7, a logic flaw in the OPNsense lockout_handler allows an unauthenticated attacker to continuously reset the authentication failure counter for their IP address. By interjecting a crafted username containing a success keyword (\\\"Accepted\\\" or \\\"Successful login\\\") between normal brute-force attempts, an attacker can prevent the failure counter from ever reaching the lockout threshold. This vulnerability is fixed in 26.1.7.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-307\", \"description\": \"CWE-307: Improper Restriction of Excessive Authentication Attempts\"}]}], \"providerMetadata\": {\"orgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"shortName\": \"GitHub_M\", \"dateUpdated\": \"2026-05-13T21:52:42.373Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-44195\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-05-14T13:46:30.721Z\", \"dateReserved\": \"2026-05-05T15:13:47.570Z\", \"assignerOrgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"datePublished\": \"2026-05-13T21:52:42.373Z\", \"assignerShortName\": \"GitHub_M\"}",
      "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.