### [CVE-2018-0739](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-0739)
![](https://img.shields.io/static/v1?label=Product&message=OpenSSL&color=blue)
![](https://img.shields.io/static/v1?label=Version&message=n%2Fa&color=blue)
![](https://img.shields.io/static/v1?label=Vulnerability&message=Stack%20overflow&color=brighgreen)

### Description

Constructed ASN.1 types with a recursive definition (such as can be found in PKCS7) could eventually exceed the stack given malicious input with excessive recursion. This could result in a Denial Of Service attack. There are no such structures used within SSL/TLS that come from untrusted sources so this is considered safe. Fixed in OpenSSL 1.1.0h (Affected 1.1.0-1.1.0g). Fixed in OpenSSL 1.0.2o (Affected 1.0.2b-1.0.2n).

### POC

#### Reference
- http://www.oracle.com/technetwork/security-advisory/cpujul2018-4258247.html
- http://www.oracle.com/technetwork/security-advisory/cpujul2018-4258247.html
- http://www.oracle.com/technetwork/security-advisory/cpuoct2018-4428296.html
- http://www.oracle.com/technetwork/security-advisory/cpuoct2018-4428296.html
- https://www.oracle.com//security-alerts/cpujul2021.html
- https://www.oracle.com//security-alerts/cpujul2021.html
- https://www.oracle.com/technetwork/security-advisory/cpujan2019-5072801.html
- https://www.oracle.com/technetwork/security-advisory/cpujan2019-5072801.html
- https://www.tenable.com/security/tns-2018-04
- https://www.tenable.com/security/tns-2018-04
- https://www.tenable.com/security/tns-2018-06
- https://www.tenable.com/security/tns-2018-06
- https://www.tenable.com/security/tns-2018-07
- https://www.tenable.com/security/tns-2018-07

#### Github
- https://github.com/ARPSyndicate/cvemon
- https://github.com/chnzzh/OpenSSL-CVE-lib
- https://github.com/tlsresearch/TSI