CVE-2024-6387: Openssh: regresshion - race condition in ssh allows rce/dos

Modified

AliasesALPINE-CVE-2024-6387MGASA-2024-0250SUSE-SU-2024:2275-1+9 more

Published 01-07-2024Last modified 15-10-2026

Vulnerability summary

CVE-2024-6387 is a high (CVSS 8.1) Signal Handler Race Condition vulnerability in almalinux. EPSS estimates a 99.51% chance of exploitation in the next 30 days, higher than 99.9% of scored vulnerabilities. 9 public exploits are recorded.

Priority

Prioritisepublic exploit

Public exploit (exploit-database, 22-04-2025)

Source freshness unavailable

How is this decided?

CVSS score

8.1/10

010

High · v3.1 (CVE.org)

EPSS score

99.51%

0%100%

Critical · 0.00 pp in 30 days

KEVNot listedNot listed by any tracked catalog.

RansomwareNot flaggedNo ransomware use recorded.

Public exploits9reference, exploit-database

Advisory lineage

Upstream 0 · Downstream 1 · Related 1

SUSE-SU-2025:20009-1

Timeline

01-07-2024
PublishedVulnerability first disclosed.
15-10-2026
Last modifiedVulnerability information updated.

Description

A security regression (CVE-2006-5051) was discovered in OpenSSH's server (sshd). There is a race condition which can lead sshd to handle some signals in an unsafe manner. An unauthenticated, remote attacker may be able to trigger it by failing to authenticate within a set time period.

CVSS metrics

6 scores · 6 sources · 1 version

v3.18.1

EPSS trend

Probability

99.51%

Chance of exploitation in the next 30 days

Percentile

100%

Versus all other CVEs

30-day change

No change 0.00 pp

From 99.51% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs

CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

9 found

referenceUnverified
Exploit Reference (santandersecurityresearch.github.io)
Maturity: unknown
referenceUnverified
Exploit Reference (qualys.com)
Maturity: unknown
referenceUnverified
Exploit Reference (vicarius.io)
Maturity: unknown

Show all 9 exploits

referenceUnverified
Exploit Reference (openwall.com)
Maturity: unknown
referenceUnverified
Exploit Reference (openwall.com)
Maturity: unknown
referenceUnverified
Exploit Reference (openwall.com)
Maturity: unknown
referenceUnverified
Exploit Reference (openwall.com)
Maturity: unknown
referenceUnverified
Exploit Reference (openwall.com)
Maturity: unknown
exploit-databaseremotelinuxUnverified
OpenSSH server (sshd) 9.8p1 - Race Condition
Maturity: poc

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

Netapp27 products

Show all 27

Redhat24 products

enterprise_linux9.0
enterprise_linux_eus9.4
enterprise_linux_for_arm_649.0_aarch64
enterprise_linux_for_arm_64_eus9.4_aarch64
enterprise_linux_for_ibm_z_systems9.0_s390x

Show all 24

Sonicwall6 products

Show all 6

Opensuse3 products

openssh-askpass-gnome&distro=openSUSE Leap 15.6< 9.6p1-150600.6.3.1
openssh&distro=openSUSE Leap 15.6< 9.6p1-150600.6.3.1
openssh&distro=openSUSE Tumbleweed< 9.6p1-10.1

Suse3 products

openssh-askpass-gnome&distro=SUSE Linux Enterprise Module for Desktop Applications 15 SP6< 9.6p1-150600.6.3.1
openssh&distro=SUSE Linux Enterprise Module for Basesystem 15 SP6< 9.6p1-150600.6.3.1
linux_enterprise_micro6.0

Debian2 products

openssh< 1:9.2p1-2+deb12u3 | < 1:9.7p1-7
debian_linux12.0

Almalinux1 product

almalinux9.0

Alpine1 product

openssh≥ 8.6, < 9.1_p1-r6 | ≥ 8.6, < 9.3_p2-r2 | ≥ 8.6, < 9.6_p1-r1 | ≥ 8.6, < 9.7_p1-r4 | ≥ 8.6, < 9.8_p1-r0

Amazon1 product

amazon_linux2023.0

Apple1 product

macos≥ 12.0, < 12.7.6 | ≥ 13.0, < 13.6.8 | ≥ 14.0, < 14.6

Arista1 product

eos≥ 4.32.0, ≤ 4.32.1f

Canonical1 product

ubuntu_linuxEOL23.10 | 24.04 | 22.04 | 22.10 | 23.04

Freebsd1 product

freebsdEOL13.2 | 13.2:p1 | 13.2:p10 | 13.2:p11 | 13.2:p2 | 13.2:p3 | 13.2:p4 | 13.2:p5 | 13.2:p6 | 13.2:p7 | 13.2:p8 | 13.2:p9 | 13.3 | 13.3:p1 | 13.3:p2 | 13.3:p3 | 14.0 | 14.0:beta5 | 14.0:p1 | 14.0:p2 | 14.0:p3 | 14.0:p4 | 14.0:p5 | 14.0:p6 | 14.0:p7 | 14.0:rc3 | 14.0:rc4-p1 | 14.1 | 14.1:p1

Mageia1 product

openssh< 9.3p1-2.2.mga9

Netbsd1 product

netbsd≤ 10.0.0

Openbsd1 product

openssh< 4.4 | ≥ 8.6, ≤ 9.8 | 4.4 | 8.5:p1 | 8.6

Ubuntu1 product

openssh< 1:8.9p1-3ubuntu0.10 | < 1:9.6p1-3ubuntu13.3

17 vendors · 76 products

References

97 links

access.redhat.com/errata/RHSA-2024:4312Vendor AdvisoryX Refsource REDHATAdvisoryThird Party Advisory
access.redhat.com/errata/RHSA-2024:4340Vendor AdvisoryX Refsource REDHATAdvisoryThird Party Advisory
access.redhat.com/errata/RHSA-2024:4389Vendor AdvisoryX Refsource REDHATAdvisoryThird Party Advisory
access.redhat.com/errata/RHSA-2024:4469Vendor AdvisoryX Refsource REDHATThird Party Advisory
access.redhat.com/errata/RHSA-2024:4474Vendor AdvisoryX Refsource REDHATThird Party Advisory
access.redhat.com/errata/RHSA-2024:4479Vendor AdvisoryX Refsource REDHATThird Party Advisory
access.redhat.com/errata/RHSA-2024:4484Vendor AdvisoryX Refsource REDHATThird Party Advisory
access.redhat.com/security/cve/CVE-2024-6387VDB EntryX Refsource REDHATREPORTThird Party Advisory
bugzilla.redhat.com/show_bug.cgi?id=2294604Issue TrackingX Refsource REDHATREPORTThird Party Advisory
santandersecurityresearch.github.io/blog/sshing_the_masses.htmlARTICLEExploitThird Party Advisory

Show all 97 references

www.openssh.com/txt/release-9.8ARTICLERelease NotesThird Party Advisory
www.qualys.com/2024/07/01/cve-2024-6387/regresshion.txtARTICLEREPORTExploitThird Party Advisory
www.vicarius.io/vsociety/posts/regresshion-an-openssh-regression-error-cve-2024-6387ExploitThird Party Advisory
www.exploit-db.com/exploits/52269Exploit
packetstorm.news/files/id/190587/Broken Link
www.openwall.com/lists/oss-security/2024/07/01/12X TransferredMailing List
www.openwall.com/lists/oss-security/2024/07/01/13X TransferredMailing List
www.openwall.com/lists/oss-security/2024/07/02/1X TransferredMailing List
www.openwall.com/lists/oss-security/2024/07/03/1X TransferredMailing List
www.openwall.com/lists/oss-security/2024/07/03/11X TransferredExploitMailing List
www.openwall.com/lists/oss-security/2024/07/03/2X TransferredMailing List
www.openwall.com/lists/oss-security/2024/07/03/3X TransferredMailing ListPatch
www.openwall.com/lists/oss-security/2024/07/03/4X TransferredMailing List
www.openwall.com/lists/oss-security/2024/07/03/5X TransferredMailing List
www.openwall.com/lists/oss-security/2024/07/04/1X TransferredMailing List
www.openwall.com/lists/oss-security/2024/07/04/2X TransferredExploitMailing List
www.openwall.com/lists/oss-security/2024/07/08/2X TransferredExploitMailing List
www.openwall.com/lists/oss-security/2024/07/08/3X TransferredMailing List
www.openwall.com/lists/oss-security/2024/07/09/2X TransferredMailing List
www.openwall.com/lists/oss-security/2024/07/09/5X TransferredExploitMailing List
www.openwall.com/lists/oss-security/2024/07/10/1X TransferredExploitMailing List
www.openwall.com/lists/oss-security/2024/07/10/2X TransferredMailing List
www.openwall.com/lists/oss-security/2024/07/10/3X TransferredMailing List
www.openwall.com/lists/oss-security/2024/07/10/4X TransferredMailing List
www.openwall.com/lists/oss-security/2024/07/10/6X TransferredMailing List
www.openwall.com/lists/oss-security/2024/07/11/1X TransferredMailing List
www.openwall.com/lists/oss-security/2024/07/11/3X TransferredMailing List
www.openwall.com/lists/oss-security/2024/07/23/4X TransferredMailing List
www.openwall.com/lists/oss-security/2024/07/23/6X TransferredMailing List
www.openwall.com/lists/oss-security/2024/07/28/2X TransferredMailing List
www.openwall.com/lists/oss-security/2024/07/28/3X TransferredMailing List
archlinux.org/news/the-sshd-service-needs-to-be-restarted-after-upgrading-to-openssh-98p1/X TransferredThird Party Advisory
arstechnica.com/security/2024/07/regresshion-vulnerability-in-openssh-gives-attackers-root-on-linux/X TransferredPress/Media CoverageThird Party Advisory
blog.qualys.com/vulnerabilities-threat-research/…X TransferredPress/Media CoverageThird Party Advisory
explore.alas.aws.amazon.com/CVE-2024-6387.htmlX TransferredThird Party Advisory
forum.vmssoftware.com/viewtopic.php?f=8&t=9132X TransferredIssue Tracking
ftp.netbsd.org/pub/NetBSD/security/advisories/NetBSD-SA2024-002.txt.ascX TransferredRelease Notes
github.com/AlmaLinux/updates/issues/629X TransferredIssue Tracking
github.com/Azure/AKS/issues/4379X TransferredIssue Tracking
github.com/PowerShell/Win32-OpenSSH/discussions/2248X TransferredIssue Tracking
github.com/PowerShell/Win32-OpenSSH/issues/2249X TransferredIssue Tracking
github.com/microsoft/azurelinux/issues/9555X TransferredIssue Tracking
github.com/openela-main/openssh/commit/e1f438970e5a337a17070a637c1b9e19697cad09X TransferredPatch
github.com/oracle/oracle-linux/issues/149X TransferredIssue Tracking
github.com/rapier1/hpn-ssh/issues/87X TransferredIssue Tracking
github.com/zgzhang/cve-2024-6387-pocX TransferredThird Party Advisory
lists.almalinux.org/archives/…X TransferredThird Party Advisory
lists.mindrot.org/pipermail/openssh-unix-announce/2024-July/000158.htmlX TransferredMailing ListRelease Notes
lists.mindrot.org/pipermail/openssh-unix-dev/2024-July/041431.htmlX TransferredMailing ListPatch
news.ycombinator.com/item?id=40843778X TransferredIssue TrackingPatch
psirt.global.sonicwall.com/vuln-detail/SNWLID-2024-0010X TransferredThird Party Advisory
security-tracker.debian.org/tracker/CVE-2024-6387X TransferredAdvisoryThird Party Advisory
security.netapp.com/advisory/ntap-20240701-0001/X TransferredThird Party Advisory
sig-security.rocky.page/issues/CVE-2024-6387/X TransferredThird Party Advisory
stackdiary.com/openssh-race-condition-in-sshd-allows-remote-code-execution/X TransferredPress/Media CoverageThird Party Advisory
ubuntu.com/security/CVE-2024-6387X TransferredREPORTThird Party Advisory
ubuntu.com/security/notices/USN-6859-1X TransferredAdvisoryThird Party Advisory
www.akamai.com/blog/security-research/2024-openssh-vulnerability-regression-what-to-know-and-doX TransferredThird Party Advisory
www.arista.com/en/support/advisories-notices/security-advisory/19904-security-advisory-0100X TransferredThird Party Advisory
www.freebsd.org/security/advisories/FreeBSD-SA-24:04.openssh.ascX TransferredThird Party Advisory
www.splunk.com/en_us/blog/security/cve-2024-6387-regresshion-vulnerability.htmlX TransferredThird Party Advisory
www.suse.com/security/cve/CVE-2024-6387.htmlX TransferredThird Party Advisory
www.theregister.com/2024/07/01/regresshion_openssh/X TransferredPress/Media CoverageThird Party Advisory
support.apple.com/kb/HT214119X TransferredThird Party Advisory
support.apple.com/kb/HT214118X TransferredThird Party Advisory
support.apple.com/kb/HT214120X TransferredThird Party Advisory
seclists.org/fulldisclosure/2024/Jul/20X TransferredMailing List
seclists.org/fulldisclosure/2024/Jul/18X TransferredMailing List
seclists.org/fulldisclosure/2024/Jul/19X TransferredMailing List
cert-portal.siemens.com/productcert/html/ssa-446545.html
cert-portal.siemens.com/productcert/html/ssa-082556.html
security.alpinelinux.org/vuln/CVE-2024-6387Advisory
advisories.mageia.org/MGASA-2024-0250.htmlAdvisory
bugs.mageia.org/show_bug.cgi?id=33346REPORT
lists.debian.org/debian-security-announce/2024/msg00135.htmlWEB
www.openwall.com/lists/oss-security/2024/07/01/3WEB
www.suse.com/support/update/announcement/2024/suse-su-20242275-1/Advisory
bugzilla.suse.com/1226642REPORT
www.suse.com/security/cve/CVE-2024-6387WEB
access.redhat.com/security/updates/classification/ARTICLE
security.access.redhat.com/data/csaf/v2/advisories/2024/rhsa-2024_4312.jsonAdvisory
www.cve.org/CVERecord?id=CVE-2024-6387AdvisoryREPORT
nvd.nist.gov/vuln/detail/CVE-2024-6387AdvisoryOval
security.access.redhat.com/data/csaf/v2/advisories/2024/rhsa-2024_4340.jsonAdvisory
security.access.redhat.com/data/csaf/v2/advisories/2024/rhsa-2024_4389.jsonAdvisory
ubuntu.com/blog/ubuntu-regresshion-security-fixREPORT
www.suse.com/support/update/announcement/2024/suse-su-20242275-2/Advisory