Buffer overflow in Hancom Office

CVE-2016-4296

When opening a Hangul Hcell Document (.cell) and processing a record that uses the CSSValFormat object, Hancom Office 2014 will search for an underscore ("_") character at the end of the string and write a null terminator after it. If the character is at the very end of the string, the application will mistakenly write the null-byte outside the bounds of its destination. This can result in heap corruption that can lead code execution under the context of the application

Vulnerability class: Buffer Overflow

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.022 (82.1th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 82nd percentile — 82.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2016-4296: held from 0.022 to 0.022.

EPSS over last 30 days · oldest: 0.022 · newest: 0.022 · change: 0.000

Affected products

  • Hancom Office — versions 2014 VP Trial HCell.exe Product version: 9.1.0.2176, HCellApp.dll Product version: 9.1.0.2176 HCellBook.dll Product version: 9.1.0.2176
  • Hancom Office 2014

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2016-4296?
CVE-2016-4296 is a high-severity vulnerability in Hancom Office, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 7.8/10. Published 2017-01-06.
How severe is CVE-2016-4296?
High severity. CVSS v3 base score is 7.8 out of 10.