{
  "fix": "ALSA-2021:4537",
  "url": "https://patchblox.com/security/fix/linux/alsa-2021-4537",
  "summary": "ALSA-2021:4537, released November 9, 2021, fixes 3 CVEs across 11 products. One of them is being exploited (CVE-2021-40438); 1 on CISA KEV. Patch Radar priority: Patch now.",
  "platform": "linux",
  "type": "advisory",
  "title": "Security update for 11 packages",
  "released": "2021-11-09T19:25:44Z",
  "priority": "Patch now",
  "priorityTier": 1,
  "priorityReason": "Closes CVE-2021-40438, exploited (CISA KEV, ransomware)",
  "supported": true,
  "cveCount": 3,
  "exploitedCveCount": 1,
  "kevCveCount": 1,
  "ransomwareCveCount": 1,
  "maxEpss": 0.99999,
  "maxCvss": 9.8,
  "vendorAdvisory": "https://osv.dev/vulnerability/ALSA-2021:4537",
  "appliesTo": [
    {
      "product": "httpd",
      "productUrl": "https://patchblox.com/security/product/linux/httpd",
      "release": "almalinux 8",
      "fixedVersion": "2.4.37-43.module_el8.5.0\u002B2597\u002Bc4b14997.alma",
      "supported": true
    },
    {
      "product": "httpd-devel",
      "productUrl": "https://patchblox.com/security/product/linux/httpd-devel",
      "release": "almalinux 8",
      "fixedVersion": "2.4.37-43.module_el8.5.0\u002B2597\u002Bc4b14997.alma",
      "supported": true
    },
    {
      "product": "httpd-filesystem",
      "productUrl": "https://patchblox.com/security/product/linux/httpd-filesystem",
      "release": "almalinux 8",
      "fixedVersion": "2.4.37-43.module_el8.5.0\u002B2597\u002Bc4b14997.alma",
      "supported": true
    },
    {
      "product": "httpd-manual",
      "productUrl": "https://patchblox.com/security/product/linux/httpd-manual",
      "release": "almalinux 8",
      "fixedVersion": "2.4.37-43.module_el8.5.0\u002B2597\u002Bc4b14997.alma",
      "supported": true
    },
    {
      "product": "httpd-tools",
      "productUrl": "https://patchblox.com/security/product/linux/httpd-tools",
      "release": "almalinux 8",
      "fixedVersion": "2.4.37-43.module_el8.5.0\u002B2597\u002Bc4b14997.alma",
      "supported": true
    },
    {
      "product": "mod_http2",
      "productUrl": "https://patchblox.com/security/product/linux/mod-http2",
      "release": "almalinux 8",
      "fixedVersion": "1.15.7-3.module_el8.5.0\u002B2609\u002Bb30d9eec",
      "supported": true
    },
    {
      "product": "mod_ldap",
      "productUrl": "https://patchblox.com/security/product/linux/mod-ldap",
      "release": "almalinux 8",
      "fixedVersion": "2.4.37-43.module_el8.5.0\u002B2597\u002Bc4b14997.alma",
      "supported": true
    },
    {
      "product": "mod_md",
      "productUrl": "https://patchblox.com/security/product/linux/mod-md",
      "release": "almalinux 8",
      "fixedVersion": "1:2.0.8-8.module_el8.5.0\u002B2609\u002Bb30d9eec",
      "supported": true
    },
    {
      "product": "mod_proxy_html",
      "productUrl": "https://patchblox.com/security/product/linux/mod-proxy-html",
      "release": "almalinux 8",
      "fixedVersion": "1:2.4.37-43.module_el8.5.0\u002B2597\u002Bc4b14997.alma",
      "supported": true
    },
    {
      "product": "mod_session",
      "productUrl": "https://patchblox.com/security/product/linux/mod-session",
      "release": "almalinux 8",
      "fixedVersion": "2.4.37-43.module_el8.5.0\u002B2597\u002Bc4b14997.alma",
      "supported": true
    },
    {
      "product": "mod_ssl",
      "productUrl": "https://patchblox.com/security/product/linux/mod-ssl",
      "release": "almalinux 8",
      "fixedVersion": "1:2.4.37-43.module_el8.5.0\u002B2597\u002Bc4b14997.alma",
      "supported": true
    }
  ],
  "cves": [
    {
      "cveId": "CVE-2021-40438",
      "url": "https://patchblox.com/security/cve/CVE-2021-40438",
      "title": "httpd: The httpd packages provide the Apache HTTP Server, a powerful, efficient, and extensible web server.\n\nSecurity Fix(es...",
      "priority": "Patch now",
      "severity": "important",
      "cvss": 9,
      "epss": 0.99999,
      "kev": true,
      "ransomware": true,
      "exploited": true,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-26691",
      "url": "https://patchblox.com/security/cve/CVE-2021-26691",
      "title": "httpd-tools: The httpd packages provide the Apache HTTP Server, a powerful, efficient, and extensible web server.\n\nSecurity Fix(es...",
      "priority": "High",
      "severity": "Important",
      "cvss": 9.8,
      "epss": 0.68067,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    },
    {
      "cveId": "CVE-2021-20325",
      "url": "https://patchblox.com/security/cve/CVE-2021-20325",
      "title": "httpd-tools: The httpd packages provide the Apache HTTP Server, a powerful, efficient, and extensible web server.\n\nSecurity Fix(es...",
      "priority": "High",
      "severity": "Important",
      "cvss": 9.8,
      "epss": 0.01593,
      "kev": false,
      "ransomware": false,
      "exploited": false,
      "disclosed": false
    }
  ],
  "dataAsOf": "2026-11-07T12:40:37Z"
}