Auth bypass in Linuxtv Xawtv

CVE-2020-13696

An issue was discovered in LinuxTV xawtv before 3.107. The function dev_open() in v4l-conf.c does not perform sufficient checks to prevent an unprivileged caller of the program from opening unintended filesystem paths. This allows a local attacker with access to the v4l-conf setuid-root program to test for the existence of arbitrary files and to trigger an open on arbitrary files with mode O_RDWR. To achieve this, relative path components need to be added to the device path, as demonstrated by a v4l-conf -c /dev/../root/.bash_history command.

Vulnerability class: Broken Access Control

EPSS: 0.004 (28.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.4 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

  • cve@mitre.org (Patch, x_refsource_MISC, Vendor Advisory)
  • cve@mitre.org (Patch, x_refsource_MISC, Vendor Advisory)
  • cve@mitre.org (Patch, x_refsource_MISC, Vendor Advisory)
  • cve@mitre.org (Third Party Advisory, x_refsource_MISC, Issue Tracking, Broken Link)
  • cve@mitre.org (x_refsource_CONFIRM, Mailing List, Third Party Advisory, Issue Tracking)
  • cve@mitre.org (vendor-advisory, Mailing List, Third Party Advisory, x_refsource_SUSE)
  • cve@mitre.org (vendor-advisory, Mailing List, Third Party Advisory, x_refsource_SUSE)
  • cve@mitre.org (mailing-list, x_refsource_MLIST, Mailing List, Third Party Advisory)
  • cve@mitre.org (x_refsource_UBUNTU, vendor-advisory, Third Party Advisory)
  • cve@mitre.org (x_refsource_FEDORA, vendor-advisory)

Frequently asked questions

What is CVE-2020-13696?
CVE-2020-13696 is a medium-severity vulnerability in Linuxtv Xawtv, classified under Incorrect Authorization. CVSS score: 4.4/10. Published 2020-06-08.
How severe is CVE-2020-13696?
Medium severity. CVSS v3 base score is 4.4 out of 10.
Is CVE-2020-13696 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.