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CVE-2026-66883 (GCVE-0-2026-66883)

Vulnerability from cvelistv5 – Published: 2026-08-04 11:46 – Updated: 2026-08-04 12:27
VLAI
Title
Oidcc.Plug.Authorize user agent session binding inert due to case-sensitive header lookup
Summary
Improper Handling of Case Sensitivity vulnerability in Erlang Ecosystem Foundation oidcc_plug (Oidcc.Plug.Authorize module) renders the user agent session binding inert, removing a defense in depth control against replay of a stolen session. This vulnerability is associated with program files lib/oidcc/plug/authorize.ex and lib/oidcc/plug/authorization_callback.ex, and program routines Oidcc.Plug.Authorize.call/2 and Oidcc.Plug.AuthorizationCallback.call/2. Oidcc.Plug.Authorize.call/2 reads the initiating client's user agent with get_req_header(conn, "User-Agent"). Plug lowercases incoming header names, but get_req_header/2 matches the supplied key exactly and performs no normalization of its own, so the mixed-case lookup always returns an empty list and nil is written into the session. On the callback side, Oidcc.Plug.AuthorizationCallback treats a stored nil user agent as nothing to compare and returns :ok without inspecting the request. The two behaviours combine so that the check passes unconditionally on every request, including for deployments that explicitly opted in with check_useragent: true, and an authorization callback can be completed from a different user agent than the one that initiated the flow without detection. The check fails open silently, with no error and no log entry, so a deployment cannot tell the binding is absent. The impact is limited to defense in depth. The inert check does not by itself allow an attacker to complete an authorization flow; it removes one layer that would otherwise hinder use of a stolen or leaked session, such as an exfiltrated session cookie replayed from a different client. The CSRF/state, nonce, and PKCE checks are unaffected and continue to function. Deployments that never enabled check_useragent are not affected in practice, since they never expected the binding. The corresponding lookup in Oidcc.Plug.AuthorizationCallback correctly uses the lowercase key and is not affected. This issue affects oidcc_plug: from 0.1.0-alpha.3 before 0.5.0.
Severity
6.3 (Medium)
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-04 12:27 UTC
CWE
  • CWE-178 - Improper Handling of Case Sensitivity
Assigner
References
Impacted products
Vendor Product Version CPE status
Erlang Ecosystem Foundation oidcc_plug Affected: 0.1.0-alpha.3 , < 0.5.0 (semver)
    cpe:2.3:a:erlef:oidcc_plug:*:*:*:*:*:erlang:*:*
Create a notification for this product.
Erlang Ecosystem Foundation oidcc_plug Affected: 0a75fb139d8e2686d1b75e0d48962323d2181673 , < f15e52c5750aaba701104b10ed96cfac063bd557 (git)
    cpe:2.3:a:erlef:oidcc_plug:*:*:*:*:*:erlang:*:*
Create a notification for this product.
Credits
Mathias Polligkeit Jonatan Männchen / EEF Mathias Polligkeit Jonatan Männchen / EEF
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Plug lowercases incoming header names, but get_req_header/2 matches the supplied key exactly and performs no normalization of its own, so the mixed-case lookup always returns an empty list and nil is written into the session. On the callback side, Oidcc.Plug.AuthorizationCallback treats a stored nil user agent as nothing to compare and returns :ok without inspecting the request. The two behaviours combine so that the check passes unconditionally on every request, including for deployments that explicitly opted in with check_useragent: true, and an authorization callback can be completed from a different user agent than the one that initiated the flow without detection. The check fails open silently, with no error and no log entry, so a deployment cannot tell the binding is absent.\\n\\nThe impact is limited to defense in depth. The inert check does not by itself allow an attacker to complete an authorization flow; it removes one layer that would otherwise hinder use of a stolen or leaked session, such as an exfiltrated session cookie replayed from a different client. The CSRF/state, nonce, and PKCE checks are unaffected and continue to function. Deployments that never enabled check_useragent are not affected in practice, since they never expected the binding. The corresponding lookup in Oidcc.Plug.AuthorizationCallback correctly uses the lowercase key and is not affected.\\n\\nThis issue affects oidcc_plug: from 0.1.0-alpha.3 before 0.5.0.\"}],\"affected\":[{\"source\":\"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\",\"affectedData\":[{\"vendor\":\"Erlang Ecosystem Foundation\",\"product\":\"oidcc_plug\",\"defaultStatus\":\"unaffected\",\"collectionURL\":\"https://repo.hex.pm\",\"packageName\":\"oidcc_plug\",\"cpes\":[\"cpe:2.3:a:erlef:oidcc_plug:*:*:*:*:*:erlang:*:*\"],\"modules\":[\"Elixir.Oidcc.Plug.Authorize\",\"Elixir.Oidcc.Plug.AuthorizationCallback\"],\"programFiles\":[\"lib/oidcc/plug/authorize.ex\",\"lib/oidcc/plug/authorization_callback.ex\"],\"programRoutines\":[{\"name\":\"\u0027Elixir.Oidcc.Plug.Authorize\u0027:call/2\"},{\"name\":\"\u0027Elixir.Oidcc.Plug.AuthorizationCallback\u0027:call/2\"}],\"repo\":\"https://github.com/erlef/oidcc_plug\",\"packageURL\":\"pkg:hex/oidcc_plug\",\"versions\":[{\"version\":\"0.1.0-alpha.3\",\"lessThan\":\"0.5.0\",\"versionType\":\"semver\",\"status\":\"affected\"}]},{\"vendor\":\"Erlang Ecosystem Foundation\",\"product\":\"oidcc_plug\",\"defaultStatus\":\"unaffected\",\"collectionURL\":\"https://github.com\",\"packageName\":\"erlef/oidcc_plug\",\"cpes\":[\"cpe:2.3:a:erlef:oidcc_plug:*:*:*:*:*:erlang:*:*\"],\"modules\":[\"Elixir.Oidcc.Plug.Authorize\",\"Elixir.Oidcc.Plug.AuthorizationCallback\"],\"programFiles\":[\"lib/oidcc/plug/authorize.ex\",\"lib/oidcc/plug/authorization_callback.ex\"],\"programRoutines\":[{\"name\":\"\u0027Elixir.Oidcc.Plug.Authorize\u0027:call/2\"},{\"name\":\"\u0027Elixir.Oidcc.Plug.AuthorizationCallback\u0027:call/2\"}],\"repo\":\"https://github.com/erlef/oidcc_plug\",\"packageURL\":\"pkg:github/erlef/oidcc_plug\",\"versions\":[{\"version\":\"0a75fb139d8e2686d1b75e0d48962323d2181673\",\"lessThan\":\"f15e52c5750aaba701104b10ed96cfac063bd557\",\"versionType\":\"git\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV40\":[{\"source\":\"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"4.0\",\"vectorString\":\"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X\",\"baseScore\":6.3,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"HIGH\",\"attackRequirements\":\"PRESENT\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"vulnConfidentialityImpact\":\"NONE\",\"vulnIntegrityImpact\":\"LOW\",\"vulnAvailabilityImpact\":\"NONE\",\"subConfidentialityImpact\":\"NONE\",\"subIntegrityImpact\":\"NONE\",\"subAvailabilityImpact\":\"NONE\",\"exploitMaturity\":\"NOT_DEFINED\",\"confidentialityRequirement\":\"NOT_DEFINED\",\"integrityRequirement\":\"NOT_DEFINED\",\"availabilityRequirement\":\"NOT_DEFINED\",\"modifiedAttackVector\":\"NOT_DEFINED\",\"modifiedAttackComplexity\":\"NOT_DEFINED\",\"modifiedAttackRequirements\":\"NOT_DEFINED\",\"modifiedPrivilegesRequired\":\"NOT_DEFINED\",\"modifiedUserInteraction\":\"NOT_DEFINED\",\"modifiedVulnConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedVulnIntegrityImpact\":\"NOT_DEFINED\",\"modifiedVulnAvailabilityImpact\":\"NOT_DEFINED\",\"modifiedSubConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedSubIntegrityImpact\":\"NOT_DEFINED\",\"modifiedSubAvailabilityImpact\":\"NOT_DEFINED\",\"Safety\":\"NOT_DEFINED\",\"Automatable\":\"NOT_DEFINED\",\"Recovery\":\"NOT_DEFINED\",\"valueDensity\":\"NOT_DEFINED\",\"vulnerabilityResponseEffort\":\"NOT_DEFINED\",\"providerUrgency\":\"NOT_DEFINED\"}}],\"ssvcV203\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"ssvcData\":{\"timestamp\":\"2026-08-04T12:27:16.535019Z\",\"id\":\"CVE-2026-66883\",\"options\":[{\"exploitation\":\"poc\"},{\"automatable\":\"no\"},{\"technicalImpact\":\"partial\"}],\"role\":\"CISA Coordinator\",\"version\":\"2.0.3\"}}]},\"weaknesses\":[{\"source\":\"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-178\"}]}],\"references\":[{\"url\":\"https://cna.erlef.org/cves/CVE-2026-66883.html\",\"source\":\"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\"},{\"url\":\"https://github.com/erlef/oidcc_plug/commit/f15e52c5750aaba701104b10ed96cfac063bd557\",\"source\":\"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\"},{\"url\":\"https://github.com/erlef/oidcc_plug/security/advisories/GHSA-w5r8-m75h-98fc\",\"source\":\"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\"},{\"url\":\"https://osv.dev/vulnerability/EEF-CVE-2026-66883\",\"source\":\"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\"},{\"url\":\"https://github.com/erlef/oidcc_plug/security/advisories/GHSA-w5r8-m75h-98fc\",\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\"}]}}",
    "vulnrichment": {
      "containers": "{\"cna\": {\"affected\": [{\"collectionURL\": \"https://repo.hex.pm\", \"cpes\": [\"cpe:2.3:a:erlef:oidcc_plug:*:*:*:*:*:erlang:*:*\"], \"defaultStatus\": \"unaffected\", \"modules\": [\"Elixir.Oidcc.Plug.Authorize\", \"Elixir.Oidcc.Plug.AuthorizationCallback\"], \"packageName\": \"oidcc_plug\", \"packageURL\": \"pkg:hex/oidcc_plug\", \"product\": \"oidcc_plug\", \"programFiles\": [\"lib/oidcc/plug/authorize.ex\", \"lib/oidcc/plug/authorization_callback.ex\"], \"programRoutines\": [{\"name\": \"\u0027Elixir.Oidcc.Plug.Authorize\u0027:call/2\"}, {\"name\": \"\u0027Elixir.Oidcc.Plug.AuthorizationCallback\u0027:call/2\"}], \"repo\": \"https://github.com/erlef/oidcc_plug\", \"vendor\": \"Erlang Ecosystem Foundation\", \"versions\": [{\"lessThan\": \"0.5.0\", \"status\": \"affected\", \"version\": \"0.1.0-alpha.3\", \"versionType\": \"semver\"}]}, {\"collectionURL\": \"https://github.com\", \"cpes\": [\"cpe:2.3:a:erlef:oidcc_plug:*:*:*:*:*:erlang:*:*\"], \"defaultStatus\": \"unaffected\", \"modules\": [\"Elixir.Oidcc.Plug.Authorize\", \"Elixir.Oidcc.Plug.AuthorizationCallback\"], \"packageName\": \"erlef/oidcc_plug\", \"packageURL\": \"pkg:github/erlef/oidcc_plug\", \"product\": \"oidcc_plug\", \"programFiles\": [\"lib/oidcc/plug/authorize.ex\", \"lib/oidcc/plug/authorization_callback.ex\"], \"programRoutines\": [{\"name\": \"\u0027Elixir.Oidcc.Plug.Authorize\u0027:call/2\"}, {\"name\": \"\u0027Elixir.Oidcc.Plug.AuthorizationCallback\u0027:call/2\"}], \"repo\": \"https://github.com/erlef/oidcc_plug\", \"vendor\": \"Erlang Ecosystem Foundation\", \"versions\": [{\"lessThan\": \"f15e52c5750aaba701104b10ed96cfac063bd557\", \"status\": \"affected\", \"version\": \"0a75fb139d8e2686d1b75e0d48962323d2181673\", \"versionType\": \"git\"}]}], \"cpeApplicability\": [{\"nodes\": [{\"cpeMatch\": [{\"criteria\": \"cpe:2.3:a:erlef:oidcc_plug:*:*:*:*:*:erlang:*:*\", \"versionEndExcluding\": \"0.5.0\", \"versionStartIncluding\": \"0.1.0-alpha.3\", \"vulnerable\": true}], \"negate\": false, \"operator\": \"OR\"}], \"operator\": \"AND\"}], \"credits\": [{\"lang\": \"en\", \"type\": \"finder\", \"value\": \"Mathias Polligkeit\"}, {\"lang\": \"en\", \"type\": \"remediation developer\", \"value\": \"Jonatan M\\u00e4nnchen / EEF\"}, {\"lang\": \"en\", \"type\": \"remediation reviewer\", \"value\": \"Mathias Polligkeit\"}, {\"lang\": \"en\", \"type\": \"coordinator\", \"value\": \"Jonatan M\\u00e4nnchen / EEF\"}], \"descriptions\": [{\"lang\": \"en\", \"supportingMedia\": [{\"base64\": false, \"type\": \"text/html\", \"value\": \"\u003cp\u003eImproper Handling of Case Sensitivity vulnerability in Erlang Ecosystem Foundation oidcc_plug (\u003ccode\u003eOidcc.Plug.Authorize\u003c/code\u003e module) renders the user agent session binding inert, removing a defense in depth control against replay of a stolen session.\u003c/p\u003e\\n\u003cp\u003eThis vulnerability is associated with program files \u003ccode\u003elib/oidcc/plug/authorize.ex\u003c/code\u003e and \u003ccode\u003elib/oidcc/plug/authorization_callback.ex\u003c/code\u003e, and program routines \u003ccode\u003eOidcc.Plug.Authorize.call/2\u003c/code\u003e and \u003ccode\u003eOidcc.Plug.AuthorizationCallback.call/2\u003c/code\u003e.\u003c/p\u003e\\n\u003cp\u003e\u003ccode\u003eOidcc.Plug.Authorize.call/2\u003c/code\u003e reads the initiating client\u0027s user agent with \u003ccode\u003eget_req_header(conn, \\\"User-Agent\\\")\u003c/code\u003e. Plug lowercases incoming header names, but \u003ccode\u003eget_req_header/2\u003c/code\u003e matches the supplied key exactly and performs no normalization of its own, so the mixed-case lookup always returns an empty list and \u003ccode\u003enil\u003c/code\u003e is written into the session. On the callback side, \u003ccode\u003eOidcc.Plug.AuthorizationCallback\u003c/code\u003e treats a stored \u003ccode\u003enil\u003c/code\u003e user agent as nothing to compare and returns \u003ccode\u003e:ok\u003c/code\u003e without inspecting the request. The two behaviours combine so that the check passes unconditionally on every request, including for deployments that explicitly opted in with \u003ccode\u003echeck_useragent: true\u003c/code\u003e, and an authorization callback can be completed from a different user agent than the one that initiated the flow without detection. The check fails open silently, with no error and no log entry, so a deployment cannot tell the binding is absent.\u003c/p\u003e\\n\u003cp\u003eThe impact is limited to defense in depth. The inert check does not by itself allow an attacker to complete an authorization flow; it removes one layer that would otherwise hinder use of a stolen or leaked session, such as an exfiltrated session cookie replayed from a different client. The CSRF/state, nonce, and PKCE checks are unaffected and continue to function. Deployments that never enabled \u003ccode\u003echeck_useragent\u003c/code\u003e are not affected in practice, since they never expected the binding. The corresponding lookup in \u003ccode\u003eOidcc.Plug.AuthorizationCallback\u003c/code\u003e correctly uses the lowercase key and is not affected.\u003c/p\u003e\\n\u003cp\u003eThis issue affects oidcc_plug: from 0.1.0-alpha.3 before 0.5.0.\u003c/p\u003e\"}, {\"base64\": false, \"type\": \"text/markdown\", \"value\": \"Improper Handling of Case Sensitivity vulnerability in Erlang Ecosystem Foundation oidcc_plug (`Oidcc.Plug.Authorize` module) renders the user agent session binding inert, removing a defense in depth control against replay of a stolen session.\\n\\nThis vulnerability is associated with program files `lib/oidcc/plug/authorize.ex` and `lib/oidcc/plug/authorization_callback.ex`, and program routines `Oidcc.Plug.Authorize.call/2` and `Oidcc.Plug.AuthorizationCallback.call/2`.\\n\\n`Oidcc.Plug.Authorize.call/2` reads the initiating client\u0027s user agent with `get_req_header(conn, \\\"User-Agent\\\")`. Plug lowercases incoming header names, but `get_req_header/2` matches the supplied key exactly and performs no normalization of its own, so the mixed-case lookup always returns an empty list and `nil` is written into the session. On the callback side, `Oidcc.Plug.AuthorizationCallback` treats a stored `nil` user agent as nothing to compare and returns `:ok` without inspecting the request. The two behaviours combine so that the check passes unconditionally on every request, including for deployments that explicitly opted in with `check_useragent: true`, and an authorization callback can be completed from a different user agent than the one that initiated the flow without detection. The check fails open silently, with no error and no log entry, so a deployment cannot tell the binding is absent.\\n\\nThe impact is limited to defense in depth. The inert check does not by itself allow an attacker to complete an authorization flow; it removes one layer that would otherwise hinder use of a stolen or leaked session, such as an exfiltrated session cookie replayed from a different client. The CSRF/state, nonce, and PKCE checks are unaffected and continue to function. Deployments that never enabled `check_useragent` are not affected in practice, since they never expected the binding. The corresponding lookup in `Oidcc.Plug.AuthorizationCallback` correctly uses the lowercase key and is not affected.\\n\\nThis issue affects oidcc_plug: from 0.1.0-alpha.3 before 0.5.0.\"}], \"value\": \"Improper Handling of Case Sensitivity vulnerability in Erlang Ecosystem Foundation oidcc_plug (Oidcc.Plug.Authorize module) renders the user agent session binding inert, removing a defense in depth control against replay of a stolen session.\\n\\nThis vulnerability is associated with program files lib/oidcc/plug/authorize.ex and lib/oidcc/plug/authorization_callback.ex, and program routines Oidcc.Plug.Authorize.call/2 and Oidcc.Plug.AuthorizationCallback.call/2.\\n\\nOidcc.Plug.Authorize.call/2 reads the initiating client\u0027s user agent with get_req_header(conn, \\\"User-Agent\\\"). Plug lowercases incoming header names, but get_req_header/2 matches the supplied key exactly and performs no normalization of its own, so the mixed-case lookup always returns an empty list and nil is written into the session. On the callback side, Oidcc.Plug.AuthorizationCallback treats a stored nil user agent as nothing to compare and returns :ok without inspecting the request. The two behaviours combine so that the check passes unconditionally on every request, including for deployments that explicitly opted in with check_useragent: true, and an authorization callback can be completed from a different user agent than the one that initiated the flow without detection. The check fails open silently, with no error and no log entry, so a deployment cannot tell the binding is absent.\\n\\nThe impact is limited to defense in depth. The inert check does not by itself allow an attacker to complete an authorization flow; it removes one layer that would otherwise hinder use of a stolen or leaked session, such as an exfiltrated session cookie replayed from a different client. The CSRF/state, nonce, and PKCE checks are unaffected and continue to function. Deployments that never enabled check_useragent are not affected in practice, since they never expected the binding. The corresponding lookup in Oidcc.Plug.AuthorizationCallback correctly uses the lowercase key and is not affected.\\n\\nThis issue affects oidcc_plug: from 0.1.0-alpha.3 before 0.5.0.\"}], \"impacts\": [{\"capecId\": \"CAPEC-60\", \"descriptions\": [{\"lang\": \"en\", \"value\": \"CAPEC-60 Reusing Session IDs (aka Session Replay)\"}]}], \"metrics\": [{\"cvssV4_0\": {\"Automatable\": \"NOT_DEFINED\", \"Recovery\": \"NOT_DEFINED\", \"Safety\": \"NOT_DEFINED\", \"attackComplexity\": \"HIGH\", \"attackRequirements\": \"PRESENT\", \"attackVector\": \"NETWORK\", \"baseScore\": 6.3, \"baseSeverity\": \"MEDIUM\", \"privilegesRequired\": \"NONE\", \"providerUrgency\": \"NOT_DEFINED\", \"subAvailabilityImpact\": \"NONE\", \"subConfidentialityImpact\": \"NONE\", \"subIntegrityImpact\": \"NONE\", \"userInteraction\": \"NONE\", \"valueDensity\": \"NOT_DEFINED\", \"vectorString\": \"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N\", \"version\": \"4.0\", \"vulnAvailabilityImpact\": \"NONE\", \"vulnConfidentialityImpact\": \"NONE\", \"vulnIntegrityImpact\": \"LOW\", \"vulnerabilityResponseEffort\": \"NOT_DEFINED\"}, \"format\": \"CVSS\", \"scenarios\": [{\"lang\": \"en\", \"value\": \"GENERAL\"}]}], \"problemTypes\": [{\"descriptions\": [{\"cweId\": \"CWE-178\", \"description\": \"CWE-178 Improper Handling of Case Sensitivity\", \"lang\": \"en\", \"type\": \"CWE\"}]}], \"providerMetadata\": {\"orgId\": \"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\", \"shortName\": \"EEF\", \"dateUpdated\": \"2026-08-04T11:46:05.191Z\"}, \"references\": [{\"tags\": [\"vendor-advisory\", \"related\"], \"url\": \"https://github.com/erlef/oidcc_plug/security/advisories/GHSA-w5r8-m75h-98fc\"}, {\"tags\": [\"related\"], \"url\": \"https://cna.erlef.org/cves/CVE-2026-66883.html\"}, {\"tags\": [\"related\"], \"url\": \"https://osv.dev/vulnerability/EEF-CVE-2026-66883\"}, {\"tags\": [\"patch\"], \"url\": \"https://github.com/erlef/oidcc_plug/commit/f15e52c5750aaba701104b10ed96cfac063bd557\"}], \"source\": {\"discovery\": \"EXTERNAL\"}, \"title\": \"Oidcc.Plug.Authorize user agent session binding inert due to case-sensitive header lookup\"}, \"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-66883\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"poc\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-08-04T12:27:16.535019Z\"}}}], \"references\": [{\"url\": \"https://github.com/erlef/oidcc_plug/security/advisories/GHSA-w5r8-m75h-98fc\", \"tags\": [\"exploit\"]}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-08-04T12:27:37.541Z\"}}]}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-66883\", \"assignerOrgId\": \"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\", \"state\": \"PUBLISHED\", \"assignerShortName\": \"EEF\", \"dateReserved\": \"2026-07-28T04:15:10.240Z\", \"datePublished\": \"2026-08-04T11:46:05.191Z\", \"dateUpdated\": \"2026-08-04T12:27:58.024Z\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



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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

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  • 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.