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CVE-2016-9843: The crc32_big function in crc32.c in zlib 1.2.8 might allow context-dependent attackers to have unspecified…

CVE-2016-9843 is rated critical with a CVSS v3.1 base score of 9.8 and affects Zlib, along with 23 other products in NVD’s configuration data. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available.

Vulnerability description

The crc32_big function in crc32.c in zlib 1.2.8 might allow context-dependent attackers to have unspecified impact via vectors involving big-endian CRC calculation.

Severity breakdown

CVSS v3.1 9.8: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

  • Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
  • Attack complexity: Low. No special conditions; the attack can be repeated reliably.
  • Privileges required: None. No account or prior access is needed.
  • User interaction: None. No action from any user is needed.
  • Scope: Unchanged. Impact stays within the vulnerable component.
  • Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
  • Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
  • Availability impact: High. Total loss of availability; the component can be shut down.

Affected products

  • Zlib: from 1.2.0 before 1.2.9
  • Opensuse Leap: 42.1; 42.2
  • Opensuse: 13.2
  • Debian Linux: 8.0
  • Canonical Ubuntu Linux: 16.04; 18.04
  • Oracle Database Server: 18c
  • Oracle JDK: 1.6.0 update161; 1.7.0 update151; 1.8.0 update144
  • Oracle JRE: 1.6.0 update161; 1.7.0 update151; 1.8.0 update144
  • Oracle Mysql: from 5.5.0 up to and including 5.5.61; from 5.6.0 up to and including 5.6.41; from 5.7.0 up to and including 5.7.23; from 8.0.0 up to and including 8.0.12
  • Red Hat Satellite: 5.8
  • Red Hat Enterprise Linux Desktop: 6.0; 7.0
  • Red Hat Enterprise Linux Eus: 7.4; 7.5
  • Red Hat Enterprise Linux Server: 6.0; 7.0
  • Red Hat Enterprise Linux Workstation: 6.0; 7.0
  • Apple Iphone OS: before 11

References