CVE-2018-6558 Privilege Escalation in fscrypt
Attackers can gain root privileges via successful login due to incorrect group ID restoration in the fscrypt PAM module.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2018-6558?
CVE-2018-6558 is a medium-severity vulnerability in The fscrypt Project fscrypt, published on 23 Aug 2018. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
The pam_fscrypt module in fscrypt before 0.2.4 may incorrectly restore primary and supplementary group IDs to the values associated with the root user, which allows attackers to gain privileges via a successful login through certain applications that use Linux-PAM (aka pam).
Which versions are affected by CVE-2018-6558?
3 open source packages ship an affected version, including github.com/google/fscrypt. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
github.com/google/fscrypt Go | All versions | 0.2.4 |
github.com/google/fscrypt Go | All versions | 0.2.4 |
github.com/google/fscrypt Go | All versions | 0.2.4 |
Products include Google Fscrypt.
How do I fix CVE-2018-6558?
Upgrade github.com/google/fscrypt to 0.2.4 or later.
Is CVE-2018-6558 being exploited?
There is no known exploitation of CVE-2018-6558 in the wild and no public exploit code.
Other vulnerabilities in The fscrypt Project fscrypt
Sources
Also known as DEBIAN-CVE-2018-6558, GHSA-qj26-7grj-whg3, GO-2020-0027, UBUNTU-CVE-2018-6558.