Security readout for executives and security teams
Plain-English summary
CVE-2024-6387 is a high-severity OpenSSH server flaw. A remote unauthenticated attacker may trigger unsafe signal handling when login times out. Successful exploitation could allow code execution or denial of service, but the source bundle shows high attack complexity and no KEV confirmation of active exploitation.
Executive priority
Prioritize remediation for externally reachable SSH services because compromise could affect confidentiality, integrity, and availability. The urgency is high, but the provided evidence supports controlled, risk-based patching rather than emergency claims of confirmed active exploitation.
Technical view
This is a regression of CVE-2006-5051 in sshd involving a race condition during signal handling. The CVSS 3.1 score is 8.1, with network attack vector, no privileges, no user interaction, and high complexity. Red Hat lists affected RHEL 9 openssh packages and OpenShift RHCOS versions.
Likely exposure
Internet-facing Linux systems running affected OpenSSH server builds are the primary concern. The provided Red Hat data specifically flags RHEL 9 variants and OpenShift Container Platform 4.13 through 4.16 RHCOS packages as affected.
Exploitation context
The bundle does not show CISA KEV listing or confirmed active exploitation. It does include public exploit-reference URLs and research coverage, so defenders should treat exposure seriously while avoiding assumptions about reliable mass exploitation.
Researcher notes
Key validation is version and package lineage, not just the OpenSSH upstream version string. Red Hat marks several older enterprise products unaffected while RHEL 9 and specific OpenShift RHCOS builds are affected, so rely on vendor advisories for platform status.
Mitigation direction
- Apply relevant vendor updates for affected OpenSSH or platform packages.
- Restart sshd after upgrading where vendor guidance requires it.
- Prioritize internet-facing SSH services and administrative jump hosts.
- Limit SSH exposure to trusted networks where operationally feasible.
- Check Red Hat advisories for product-specific fixed package versions.
Validation and detection
- Inventory systems exposing sshd to untrusted networks.
- Compare installed OpenSSH packages against vendor affected and fixed versions.
- Verify RHEL 9 and OpenShift RHCOS versions against Red Hat advisories.
- Confirm sshd was restarted after package remediation.
- Review security monitoring for unusual SSH authentication timeout patterns.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-364: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupContainer behavior lookup
The affected technology mentions containers, so container-specific ATT&CK technique review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2024-6387 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 8.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H2.25.9redhatVulnerability scoring details
Base CVSS 3.1 score
8.1HighVector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- Source timelineredhat
Reported to Red Hat.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- Source timelineredhat
Made public.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- RHSA-2024:4312CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2024:4340CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2024:4389CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2024:4469CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2024:4474CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2024:4479CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2024:4484CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2024-6387CVE reference, redhat · vdb-entry, x_refsource_REDHAT
- RHBZ#2294604CVE reference, redhat · issue-tracking, x_refsource_REDHAT
- https://santandersecurityresearch.github.io/blog/sshing_the_masses.htmlCVE reference, redhat
- https://www.openssh.com/txt/release-9.8CVE reference, redhat
- https://www.qualys.com/2024/07/01/cve-2024-6387/regresshion.txtCVE reference, redhat
- https://www.vicarius.io/vsociety/posts/regresshion-an-openssh-regression-error-cve-2024-6387CVE reference, CVE
- https://www.exploit-db.com/exploits/52269CVE reference, CVE
- https://packetstorm.news/files/id/190587/CVE reference, CVE
- https://archlinux.org/news/the-sshd-service-needs-to-be-restarted-after-upgrading-to-openssh-98p1/CVE reference, CVE · x_transferred
- https://arstechnica.com/security/2024/07/regresshion-vulnerability-in-openssh-gives-attackers-root-on-linux/CVE reference, CVE · x_transferred
- https://blog.qualys.com/vulnerabilities-threat-research/2024/07/01/regresshion-remote-unauthenticated-code-execution-vulnerability-in-openssh-serverCVE reference, CVE · x_transferred
- https://explore.alas.aws.amazon.com/CVE-2024-6387.htmlCVE reference, CVE · x_transferred
- https://forum.vmssoftware.com/viewtopic.php?f=8&t=9132CVE reference, CVE · x_transferred
- https://ftp.netbsd.org/pub/NetBSD/security/advisories/NetBSD-SA2024-002.txt.ascCVE reference, CVE · x_transferred
- https://github.com/AlmaLinux/updates/issues/629CVE reference, CVE · x_transferred
- https://github.com/Azure/AKS/issues/4379CVE reference, CVE · x_transferred
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Signal Handler Race Condition
Signal Handler Race Condition represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.