CVE-2023-38408

Exp

The PKCS#11 feature in ssh-agent in OpenSSH before 9.3p2 has an insufficiently trustworthy search path, leading to remote code execution if an agent is forwarded to an attacker-controlled system. (Code in /usr/lib is not necessarily safe for loading into ssh-agent.) NOTE: this issue exists because of an incomplete fix for CVE-2016-10009.

Published: 2023-07-19 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-38408 is rated High Exploit Risk (94/100): CVSS Critical severity, with high exploitation likelihood (EPSS 76.77%, 99th percentile). 3 public exploit reference(s) are indexed (Exploit-DB). EPSS rose +9.92% over the last day, indicating growing attacker interest. Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2023-38408

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗
— nvd_ref exploit_tag Exploit-DB ↗
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2023-38408

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 66.85% 76.77% +9.92%
2 2026-06-14 64.35% 66.85% +2.50%
3 2026-05-27 — 64.35% —

Full EPSS history (104 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-38408

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 [email protected]
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2023-38408

OS Trackers for CVE-2023-38408

vendor priority summary link
alpine — CVE-2023-38408: 1 source package rows (openssh); 39 state rows across 6 repos (3.17-main, 3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 39, open 0. https://security.alpinelinux.org/vuln/CVE-2023-38408
debian not yet assigned CVE-2023-38408 not yet assigned priority: Debian including 1 source packages (openssh), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2023-38408
gentoo high CVE-2023-38408: 1 GLSA(s) (202307-01), 1 atom(s) (net-misc/openssh); latest impact high. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2023-38408
redhat high — https://access.redhat.com/security/cve/CVE-2023-38408
suse high CVE-2023-38408 severity important: SUSE including 351 source package names (1.11.9.0.4.7.1:openssh-8.4p1-150300.3.22.1, 1.11.9.0.4.7.1:openssh-clients-8.4p1-150300.3.22.1, …), 1191 product×package rows across 237 product lines (Container bci/nodejs, Container ses/7.1/cephcsi/cephcsi, … (237 product lines)): Fixed 1019, Known Affected 165, Known Not Affected 7. https://www.suse.com/security/cve/CVE-2023-38408/
ubuntu medium CVE-2023-38408 medium priority: Ubuntu including 2 source packages (openssh, openssh-ssh1), 26 status rows across 13 suites (bionic, focal, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): ignored 12, released 12, DNE 2. https://ubuntu.com/security/CVE-2023-38408

Affected software / configurations for CVE-2023-38408

Vendor Product Version Raw CPE
openbsd openssh < 9.3 cpe:2.3:a:openbsd:openssh:*:*:*:*:*:*:*:*
openbsd openssh 9.3 cpe:2.3:a:openbsd:openssh:9.3:-:*:*:*:*:*:*
openbsd openssh 9.3 cpe:2.3:a:openbsd:openssh:9.3:p1:*:*:*:*:*:*
fedoraproject fedora 37 cpe:2.3:o:fedoraproject:fedora:37:*:*:*:*:*:*:*
fedoraproject fedora 38 cpe:2.3:o:fedoraproject:fedora:38:*:*:*:*:*:*:*

References for CVE-2023-38408

URL Tags
http://packetstormsecurity.com/files/173661/OpenSSH-Forwarded-SSH-Agent-Remote-Code-Execution.html Exploit Third Party Advisory VDB Entry
http://www.openwall.com/lists/oss-security/2023/07/20/1 Exploit Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2023/07/20/2 Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2023/09/22/11
http://www.openwall.com/lists/oss-security/2023/09/22/9
https://blog.qualys.com/vulnerabilities-threat-research/2023/07/19/cve-2023-38408-remote-code-execution-in-opensshs-forwarded-ssh-agent Third Party Advisory
https://github.com/openbsd/src/commit/7bc29a9d5cd697290aa056e94ecee6253d3425f8 Patch
https://github.com/openbsd/src/commit/f03a4faa55c4ce0818324701dadbf91988d7351d Patch
https://github.com/openbsd/src/commit/f8f5a6b003981bb824329dc987d101977beda7ca Patch
https://lists.debian.org/debian-lts-announce/2023/08/msg00021.html
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CEBTJJINE2I3FHAUKKNQWMFGYMLSMWKQ/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RAXVQS6ZYTULFAK3TEJHRLKZALJS3AOU/
https://news.ycombinator.com/item?id=36790196 Issue Tracking Patch
https://security.gentoo.org/glsa/202307-01 Third Party Advisory
https://security.netapp.com/advisory/ntap-20230803-0010/
https://support.apple.com/kb/HT213940
https://www.openssh.com/security.html Vendor Advisory
https://www.openssh.com/txt/release-9.3p2 Release Notes
https://www.qualys.com/2023/07/19/cve-2023-38408/rce-openssh-forwarded-ssh-agent.txt Exploit Third Party Advisory
https://www.vicarius.io/vsociety/posts/exploring-opensshs-agent-forwarding-rce-cve-2023-38408
cvelogic Threat Intelligence