CVE-2023-25136

Public Exploit

Description

OpenSSH server (sshd) 9.1 introduced a double-free vulnerability during options.kex_algorithms handling. This is fixed in OpenSSH 9.2. The double free can be leveraged, by an unauthenticated remote attacker in the default configuration, to jump to any location in the sshd address space. One third-party report states "remote code execution is theoretically possible."

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 90.54% Top 5%
Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory gentoo.org Vendor Advisory openbsd.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://ftp.openbsd.org/pub/OpenBSD/patches/7.2/common/017_sshd.patch.sig patch vendor advisory
https://www.openwall.com/lists/oss-security/2023/02/02/2 mailing list third party advisory exploit
https://bugzilla.mindrot.org/show_bug.cgi?id=3522 third party advisory issue tracking exploit
https://github.com/openssh/openssh-portable/commit/486c4dc3b83b4b67d663fb0fa62bc24138ec3946 third party advisory patch
https://jfrog.com/blog/openssh-pre-auth-double-free-cve-2023-25136-writeup-and-proof-of-concept/ third party advisory exploit
https://news.ycombinator.com/item?id=34711565 third party advisory issue tracking
http://www.openwall.com/lists/oss-security/2023/02/13/1 third party advisory mailing list
http://www.openwall.com/lists/oss-security/2023/02/22/1 third party advisory mailing list
http://www.openwall.com/lists/oss-security/2023/02/22/2 third party advisory mailing list
http://www.openwall.com/lists/oss-security/2023/02/23/3 third party advisory mailing list
http://www.openwall.com/lists/oss-security/2023/03/06/1 third party advisory mailing list
http://www.openwall.com/lists/oss-security/2023/03/09/2 third party advisory mailing list
https://security.netapp.com/advisory/ntap-20230309-0003/ third party advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/R7LKQDFZWKYHQ65TBSH2X2HJQ4V2THS3/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JGAUIXJ3TEKCRKVWFQ6GDAGQFTIIGQQP/ vendor advisory
https://security.gentoo.org/glsa/202307-01 third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2023-25136?
CVE-2023-25136 has been scored as a medium severity vulnerability.
How to fix CVE-2023-25136?
To fix CVE-2023-25136, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2023-25136 being actively exploited in the wild?
It is possible that CVE-2023-25136 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~91% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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