An issue was discovered in json-c from 20200420 (post 0.14 unreleased code) through 0.15-20200726. A stack-buffer-overflow exists in the auxiliary sample program jsonparse which is located in the function parseit.

USN-4360-1 fixed a vulnerability in json-c. The security fix introduced a memory leak that was reverted in USN-4360-2 and USN-4360-3. This update provides the correct fix update for CVE-2020-12762. Original advisory details: It was discovered that json-c incorrectly handled certain JSON files. An attacker could possibly use this issue to execute arbitrary code.

json-c could allow a remote attacker to execute arbitrary code on the system, caused by an integer overflow and out-of-bounds write. By persuading a victim to run a specially crafted file, an attacker could exploit this vulnerability to execute arbitrary code on the system.

Buffer overflow in the printbuf APIs in json-c before 0.12 allows remote attackers to cause a denial of service via unspecified vectors.

Florian Weimer reported that the printbuf APIs used in the json-c library used ints for counting buffer lengths, which is inappropriate for 32bit architectures. These functions need to be changed to using sizet if possible for sizes, or to be hardened against negative values if not. This could be used to cause a denial of service in an application linked to the json-c library.

Acknowledgements:

This issue was discovered by Florian Weimer of the Red Hat Product Security Team.

CVE-2013-6370 Buffer overflow in the printbuf APIs in json-c before 0.12 allows remote attackers to cause a denial of service via unspecified vectors. CVE-2013-6371 The hash functionality in json-c before 0.12 allows context-dependent attackers to cause a denial of service (CPU consumption) via crafted JSON data, involving collisions.

Florian Weimer reported that the hash function in the json-c library was weak, and that parsing smallish JSON strings showed quadratic timing behaviour. This could cause an application linked to the json-c library, and that processes some specially-crafted JSON data, to use excessive amounts of CPU.

Acknowledgements:

This issue was discovered by Florian Weimer of the Red Hat Product Security Team.