slock allows attackers to bypass the screen lock via vectors involving an invalid password hash, which triggers a NULL pointer dereference and crash.

There are packages installed that are affected by a vulnerability referenced in the following CVE:

  - slock allows attackers to bypass the screen lock via vectors involving an invalid password hash, which
    triggers a NULL pointer dereference and crash. (CVE-2016-6866)

This release fixes CVE-2016-6866, a crash when verifying a password for a user without a valid shadow hash entry.

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.

It was discovered that the slock screen locking tool would segfault when the user's account had been disabled.

slock called crypt(3) and used the return value for strcmp(3) without checking to see if the return value of crypt(3) was a NULL pointer. If the hash returned by (getspnam()->sp_pwdp) was invalid, crypt(3) would return NULL and set errno to EINVAL. This would cause slock to segfault which leaves the machine unprotected.

For Debian 7 'Wheezy', this issue has been fixed in suckless-tools version 38-2+deb7u1.

We recommend that you upgrade your suckless-tools packages.

NOTE: Tenable Network Security has extracted the preceding description block directly from the DLA security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

ID	Name	Product	Family	Severity
407166	Alpine: multiple slock packages: security update to 1.3-r3	Tenable Cloud Security	Alpine Linux Local Security Checks	high
407166	Alpine: multiple slock packages: security update to 1.3-r3	Tenable Self-Hosted Container Security	Alpine Linux Local Security Checks	high
400966	Alpine: multiple slock packages: security update to 1.3-r2 (deprecated)	Tenable Cloud Security	Alpine Linux Local Security Checks	high
400966	Alpine: multiple slock packages: security update to 1.3-r2 (deprecated)	Tenable Self-Hosted Container Security	Alpine Linux Local Security Checks	high
94779	Fedora 25 : slock (2016-1b7e66c08b)	Nessus	Fedora Local Security Checks	high
93425	Fedora 24 : slock (2016-985b68721b)	Nessus	Fedora Local Security Checks	high
93423	Fedora 23 : slock (2016-7e817cbf55)	Nessus	Fedora Local Security Checks	high
93053	Debian DLA-598-1 : suckless-tools security update	Nessus	Debian Local Security Checks	high

Detections

Analytics

CVE-2016-6866

high

Tenable Plugins

high

high

high

high

high

high

high

high