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CVE-2017-2789: Justsystems Ichitaro: Buffer overflow
CVE-2017-2789 is rated critical with a CVSS v3.0 base score of 9.8 and affects Justsystems Ichitaro. 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
When copying filedata into a buffer, JustSystems Ichitaro Office 2016 Trial will calculate two values to determine how much data to copy from the document. If both of these values are larger than the size of the buffer, the application will choose the smaller of the two and trust it to copy data from the file. This value is larger than the buffer size, which leads to a heap-based buffer overflow. This overflow corrupts an offset in the heap used in pointer arithmetic for writing data and can lead to code execution under the context of the application.
Severity breakdown
CVSS v3.0 9.8: CVSS:3.0/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.
Underlying weakness
CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer
The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary.
Affected products
- Justsystems Ichitaro: all versions listed by NVD