Openssh: possible remote code execution due to a race condition in signal handling affecting red hat enterprise linux 9

{
  "id": "5504c6882fc0e38b20d650949c9b1b686a5adb46560ceca169634fc0fd6e888b",
  "url": "https://osv.dev/vulnerability/CVE-2024-6409",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Openssh: possible remote code execution due to a race condition in signal handling affecting red hat enterprise linux 9",
    "summary": "A race condition vulnerability was discovered in how signals are handled by OpenSSH's server (sshd). If a remote attacker does not authenticate within a set time period, then sshd's SIGALRM handler is called asynchronously. However, this signal handler calls various functions that are not async-signal-safe, for example, syslog(). As a consequence of a successful attack, in the worst case scenario, an attacker may be able to perform a remote code execution (RCE) as an unprivileged user running the sshd server.",
    "evidence": "osv:CVE-2024-6409",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2024-6409",
      "aliases": [
        "CVE-2024-6409"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/openela-main/openssh",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "c00da7741d42029e49047dd89e266d91dcfbffa0"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "fixed": "c00da7741d42029e49047dd89e266d91dcfbffa0"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  }
                ]
              }
            }
          ],
          "versions": [
            "imports/el9/openssh-8.7p1-38.el9_4.1",
            "imports/el9/openssh-8.7p1-38.el9",
            "imports/el9/openssh-8.7p1-34.el9_3.3",
            "imports/el9/openssh-8.7p1-34.el9",
            "imports/el9/openssh-8.7p1-30.el9_2"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2024-6409.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:52.565443244Z",
      "provider": "osv",
      "references": [
        "https://access.redhat.com/downloads/content/package-browser/",
        "https://catalog.redhat.com/software/containers/",
        "https://cert-portal.siemens.com/productcert/html/ssa-398330.html",
        "https://explore.alas.aws.amazon.com/CVE-2024-6409.html",
        "https://security-tracker.debian.org/tracker/CVE-2024-6409",
        "https://sig-security.rocky.page/issues/CVE-2024-6409/",
        "https://ubuntu.com/security/CVE-2024-6409",
        "https://www.openssh.com/",
        "https://www.suse.com/security/cve/CVE-2024-6409.html",
        "https://access.redhat.com/errata/RHSA-2024:4457",
        "https://access.redhat.com/errata/RHSA-2024:4613",
        "https://access.redhat.com/errata/RHSA-2024:4716",
        "https://access.redhat.com/errata/RHSA-2024:4910",
        "https://access.redhat.com/errata/RHSA-2024:4955",
        "https://access.redhat.com/errata/RHSA-2024:4960",
        "https://access.redhat.com/errata/RHSA-2024:5444",
        "https://access.redhat.com/security/cve/CVE-2024-6409",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/6xxx/CVE-2024-6409.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2024-6409",
        "https://security.netapp.com/advisory/ntap-20240712-0003/",
        "https://bugzilla.redhat.com/show_bug.cgi?id=2295085",
        "https://bugzilla.suse.com/show_bug.cgi?id=1227217",
        "https://github.com/openela-main/openssh/commit/c00da7741d42029e49047dd89e266d91dcfbffa0",
        "https://anongit.mindrot.org/openssh.git",
        "https://almalinux.org/blog/2024-07-09-cve-2024-6409/"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-364"
        ],
        "cna_assigner": "redhat",
        "unresolved_ranges": [
          {
            "extracted_events": [
              {
                "range": [
                  {
                    "fixed": "0:8.7p1-38.el9_4.4"
                  },
                  {
                    "fixed": "0:8.7p1-38.el9_4.4"
                  },
                  {
                    "fixed": "0:8.7p1-12.el9_0.3"
                  },
                  {
                    "fixed": "0:8.7p1-30.el9_2.7"
                  },
                  {
                    "fixed": "413.92.202408122222-0"
                  },
                  {
                    "fixed": "414.92.202407300859-0"
                  },
                  {
                    "fixed": "415.92.202407301159-0"
                  },
                  {
                    "fixed": "416.94.202407171205-0"
                  }
                ],
                "source": "AFFECTED_FIELD",
                "strategy": "InverseAffectedRanges"
              }
            ]
          }
        ],
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/6xxx/CVE-2024-6409.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2024-6409",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 521203,
  "published_at": "2024-07-08T17:57:10.517+00:00"
}