CVE-2020-12762: canonical ubuntu_linux Integer Overflow or Wraparound

Vulnerability summary

CVE-2020-12762 is a high (CVSS 7.8) Integer Overflow or Wraparound vulnerability in canonical ubuntu_linux. EPSS estimates a 1.90% chance of exploitation in the next 30 days, higher than 79.2% of scored vulnerabilities. 2 public exploits are recorded.

Timeline

1. 09-05-2020
   PublishedVulnerability first disclosed.
2. 14-10-2026
   Last modifiedVulnerability information updated.

Description

json-c through 0.14 has an integer overflow and out-of-bounds write via a large JSON file, as demonstrated by printbuf_memappend.

• CWE-190Integer Overflow or WraparoundThe product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.
• CWE-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.