ID CVE-2018-20685
Summary In OpenSSH 7.9, scp.c in the scp client allows remote SSH servers to bypass intended access restrictions via the filename of . or an empty filename. The impact is modifying the permissions of the target directory on the client side.
References
Vulnerable Configurations
  • OpenBSD OpenSSH 7.9
    cpe:2.3:a:openbsd:openssh:7.9
  • cpe:2.3:a:winscp:winscp:5.13
    cpe:2.3:a:winscp:winscp:5.13
  • cpe:2.3:a:netapp:cloud_backup
    cpe:2.3:a:netapp:cloud_backup
  • cpe:2.3:a:netapp:element_software
    cpe:2.3:a:netapp:element_software
  • cpe:2.3:a:netapp:ontap_select_deploy
    cpe:2.3:a:netapp:ontap_select_deploy
  • cpe:2.3:a:netapp:steelstore_cloud_integrated_storage
    cpe:2.3:a:netapp:steelstore_cloud_integrated_storage
  • cpe:2.3:a:netapp:storage_automation_store
    cpe:2.3:a:netapp:storage_automation_store
  • Debian Linux 9.0
    cpe:2.3:o:debian:debian_linux:9.0
  • Canonical Ubuntu Linux 14.04 LTS (Long-Term Support)
    cpe:2.3:o:canonical:ubuntu_linux:14.04:-:-:-:lts
  • Canonical Ubuntu Linux 16.04 LTS (Long-Term Support)
    cpe:2.3:o:canonical:ubuntu_linux:16.04:-:-:-:lts
  • Canonical Ubuntu Linux 18.04 LTS Edition
    cpe:2.3:o:canonical:ubuntu_linux:18.04:-:-:-:lts
  • Canonical Ubuntu Linux 18.10
    cpe:2.3:o:canonical:ubuntu_linux:18.10
CVSS
Base: 2.6
Impact:
Exploitability:
CWE CWE-284
CAPEC
  • Embedding Scripts within Scripts
    An attack of this type exploits a programs' vulnerabilities that are brought on by allowing remote hosts to execute scripts. The attacker leverages this capability to execute scripts to execute his/her own script by embedding it within other scripts that the target software is likely to execute. The attacker must have the ability to inject script into script that is likely to be executed. If this is done, then the attacker can potentially launch a variety of probes and attacks against the web server's local environment, in many cases the so-called DMZ, back end resources the web server can communicate with, and other hosts. With the proliferation of intermediaries, such as Web App Firewalls, network devices, and even printers having JVMs and Web servers, there are many locales where an attacker can inject malicious scripts. Since this attack pattern defines scripts within scripts, there are likely privileges to execute said attack on the host. Of course, these attacks are not solely limited to the server side, client side scripts like Ajax and client side JavaScript can contain malicious scripts as well. In general all that is required is for there to be sufficient privileges to execute a script, but not protected against writing.
  • Signature Spoofing by Key Theft
    An attacker obtains an authoritative or reputable signer's private signature key by theft and then uses this key to forge signatures from the original signer to mislead a victim into performing actions that benefit the attacker.
nessus via4
  • NASL family Huawei Local Security Checks
    NASL id EULEROS_SA-2019-1038.NASL
    description According to the version of the openssh packages installed, the EulerOS installation on the remote host is affected by the following vulnerability : - In OpenSSH 7.9, scp.c in the scp client allows remote SSH servers to bypass intended access restrictions via the filename of . or an empty filename. The impact is modifying the permissions of the target directory on the client side.(CVE-2018-20685) Note that Tenable Network Security has extracted the preceding description block directly from the EulerOS security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen 2019-02-21
    modified 2019-02-15
    plugin id 122211
    published 2019-02-15
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=122211
    title EulerOS 2.0 SP5 : openssh (EulerOS-SA-2019-1038)
  • NASL family SuSE Local Security Checks
    NASL id SUSE_SU-2019-13931-1.NASL
    description This update for openssh fixes the following issues : Security issue fixed : CVE-2018-20685: Fixed an issue where scp client allows remote SSH servers to bypass intended access restrictions (bsc#1121571) CVE-2019-6109: Fixed an issue where the scp client would allow malicious remote SSH servers to manipulate terminal output via the object name, e.g. by inserting ANSI escape sequences (bsc#1121816) CVE-2019-6110: Fixed an issue where the scp client would allow malicious remote SSH servers to manipulate stderr output, e.g. by inserting ANSI escape sequences (bsc#1121818) CVE-2019-6111: Fixed an issue where the scp client would allow malicious remote SSH servers to execute directory traversal attacks and overwrite files (bsc#1121821) Note that Tenable Network Security has extracted the preceding description block directly from the SUSE security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen 2019-02-21
    modified 2019-02-20
    plugin id 121306
    published 2019-01-22
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=121306
    title SUSE SLES11 Security Update : openssh (SUSE-SU-2019:13931-1)
  • NASL family SuSE Local Security Checks
    NASL id SUSE_SU-2019-0126-1.NASL
    description This update for openssh fixes the following issues : Security issues fixed : CVE-2018-20685: Fixed an issue where scp client allows remote SSH servers to bypass intended access restrictions (bsc#1121571) CVE-2019-6109: Fixed an issue where the scp client would allow malicious remote SSH servers to manipulate terminal output via the object name, e.g. by inserting ANSI escape sequences (bsc#1121816) CVE-2019-6110: Fixed an issue where the scp client would allow malicious remote SSH servers to manipulate stderr output, e.g. by inserting ANSI escape sequences (bsc#1121818) CVE-2019-6111: Fixed an issue where the scp client would allow malicious remote SSH servers to execute directory traversal attacks and overwrite files (bsc#1121821) Note that Tenable Network Security has extracted the preceding description block directly from the SUSE security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen 2019-02-21
    modified 2019-02-20
    plugin id 121296
    published 2019-01-22
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=121296
    title SUSE SLED15 / SLES15 Security Update : openssh (SUSE-SU-2019:0126-1)
  • NASL family SuSE Local Security Checks
    NASL id OPENSUSE-2019-91.NASL
    description This update for openssh fixes the following issues : Security issues fixed : - CVE-2018-20685: Fixed an issue where scp client allows remote SSH servers to bypass intended access restrictions (bsc#1121571) - CVE-2019-6109: Fixed an issue where the scp client would allow malicious remote SSH servers to manipulate terminal output via the object name, e.g. by inserting ANSI escape sequences (bsc#1121816) - CVE-2019-6110: Fixed an issue where the scp client would allow malicious remote SSH servers to manipulate stderr output, e.g. by inserting ANSI escape sequences (bsc#1121818) - CVE-2019-6111: Fixed an issue where the scp client would allow malicious remote SSH servers to execute directory traversal attacks and overwrite files (bsc#1121821) This update was imported from the SUSE:SLE-15:Update update project.
    last seen 2019-02-21
    modified 2019-02-20
    plugin id 121430
    published 2019-01-29
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=121430
    title openSUSE Security Update : openssh (openSUSE-2019-91)
  • NASL family SuSE Local Security Checks
    NASL id SUSE_SU-2019-0132-1.NASL
    description This update for openssh fixes the following issues : Security issue fixed : CVE-2018-20685: Fixed an issue where scp client allows remote SSH servers to bypass intended access restrictions (bsc#1121571) CVE-2019-6109: Fixed an issue where the scp client would allow malicious remote SSH servers to manipulate terminal output via the object name, e.g. by inserting ANSI escape sequences (bsc#1121816) CVE-2019-6110: Fixed an issue where the scp client would allow malicious remote SSH servers to manipulate stderr output, e.g. by inserting ANSI escape sequences (bsc#1121818) CVE-2019-6111: Fixed an issue where the scp client would allow malicious remote SSH servers to execute directory traversal attacks and overwrite files (bsc#1121821) Note that Tenable Network Security has extracted the preceding description block directly from the SUSE security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen 2019-02-21
    modified 2019-02-20
    plugin id 121300
    published 2019-01-22
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=121300
    title SUSE SLED12 / SLES12 Security Update : openssh (SUSE-SU-2019:0132-1)
  • NASL family Debian Local Security Checks
    NASL id DEBIAN_DSA-4387.NASL
    description Harry Sintonen from F-Secure Corporation discovered multiple vulnerabilities in OpenSSH, an implementation of the SSH protocol suite. All the vulnerabilities are in found in the scp client implementing the SCP protocol. - CVE-2018-20685 Due to improper directory name validation, the scp client allows servers to modify permissions of the target directory by using empty or dot directory name. - CVE-2019-6109 Due to missing character encoding in the progress display, the object name can be used to manipulate the client output, for example to employ ANSI codes to hide additional files being transferred. - CVE-2019-6111 Due to scp client insufficient input validation in path names sent by server, a malicious server can do arbitrary file overwrites in target directory. If the recursive (-r) option is provided, the server can also manipulate subdirectories as well. The check added in this version can lead to regression if the client and the server have differences in wildcard expansion rules. If the server is trusted for that purpose, the check can be disabled with a new -T option to the scp client.
    last seen 2019-02-21
    modified 2019-02-20
    plugin id 122068
    published 2019-02-11
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=122068
    title Debian DSA-4387-1 : openssh - security update
  • NASL family SuSE Local Security Checks
    NASL id OPENSUSE-2019-93.NASL
    description This update for openssh fixes the following issues : Security issue fixed : - CVE-2018-20685: Fixed an issue where scp client allows remote SSH servers to bypass intended access restrictions (bsc#1121571) - CVE-2019-6109: Fixed an issue where the scp client would allow malicious remote SSH servers to manipulate terminal output via the object name, e.g. by inserting ANSI escape sequences (bsc#1121816) - CVE-2019-6110: Fixed an issue where the scp client would allow malicious remote SSH servers to manipulate stderr output, e.g. by inserting ANSI escape sequences (bsc#1121818) - CVE-2019-6111: Fixed an issue where the scp client would allow malicious remote SSH servers to execute directory traversal attacks and overwrite files (bsc#1121821) This update was imported from the SUSE:SLE-12-SP2:Update update project.
    last seen 2019-02-21
    modified 2019-02-20
    plugin id 121460
    published 2019-01-30
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=121460
    title openSUSE Security Update : openssh (openSUSE-2019-93)
  • NASL family Ubuntu Local Security Checks
    NASL id UBUNTU_USN-3885-1.NASL
    description Harry Sintonen discovered multiple issues in the OpenSSH scp utility. If a user or automated system were tricked into connecting to an untrusted server, a remote attacker could possibly use these issues to write to arbitrary files, change directory permissions, and spoof client output. Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen 2019-02-21
    modified 2019-02-20
    plugin id 122055
    published 2019-02-08
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=122055
    title Ubuntu 14.04 LTS / 16.04 LTS / 18.04 LTS / 18.10 : openssh vulnerabilities (USN-3885-1)
  • NASL family Fedora Local Security Checks
    NASL id FEDORA_2019-F6FF819834.NASL
    description This update fixes CVE-2018-20685 (the first 'variant') and backports several fixes to unbreak ECDSA authentication from PKCS#11, certificate authentication and so on. Note that Tenable Network Security has extracted the preceding description block directly from the Fedora update system website. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen 2019-02-21
    modified 2019-01-30
    plugin id 121197
    published 2019-01-16
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=121197
    title Fedora 29 : openssh (2019-f6ff819834)
  • NASL family Fedora Local Security Checks
    NASL id FEDORA_2019-9EB0AE6296.NASL
    description This update fixes CVE-2018-20685 (the first 'variant'). Note that Tenable Network Security has extracted the preceding description block directly from the Fedora update system website. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen 2019-02-21
    modified 2019-01-30
    plugin id 121262
    published 2019-01-22
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=121262
    title Fedora 28 : openssh (2019-9eb0ae6296)
  • NASL family SuSE Local Security Checks
    NASL id SUSE_SU-2019-0125-1.NASL
    description This update for openssh fixes the following issues : Security issue fixed : CVE-2018-20685: Fixed an issue where scp client allows remote SSH servers to bypass intended access restrictions (bsc#1121571) CVE-2019-6109: Fixed an issue where the scp client would allow malicious remote SSH servers to manipulate terminal output via the object name, e.g. by inserting ANSI escape sequences (bsc#1121816) CVE-2019-6110: Fixed an issue where the scp client would allow malicious remote SSH servers to manipulate stderr output, e.g. by inserting ANSI escape sequences (bsc#1121818) CVE-2019-6111: Fixed an issue where the scp client would allow malicious remote SSH servers to execute directory traversal attacks and overwrite files (bsc#1121821) Note that Tenable Network Security has extracted the preceding description block directly from the SUSE security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen 2019-02-21
    modified 2019-02-20
    plugin id 121295
    published 2019-01-22
    reporter Tenable
    source https://www.tenable.com/plugins/index.php?view=single&id=121295
    title SUSE SLES12 Security Update : openssh (SUSE-SU-2019:0125-1)
refmap via4
bid 106531
confirm https://security.netapp.com/advisory/ntap-20190215-0001/
debian DSA-4387
gentoo GLSA-201903-16
misc
ubuntu USN-3885-1
the hacker news via4
id THN:445A5A09D3930F981A45FE5AFA1E4CEC
last seen 2019-01-15
modified 2019-01-15
published 2019-01-15
reporter The Hacker News
source https://thehackernews.com/2019/01/scp-software-vulnerabilities.html
title 36-Year-Old SCP Clients' Implementation Flaws Discovered
Last major update 10-01-2019 - 16:29
Published 10-01-2019 - 16:29
Last modified 25-03-2019 - 12:29
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