CVE-2020-5243 : Security Advisory and Response
Learn about CVE-2020-5243, a Medium severity denial of service vulnerability in uap-core < 0.7.3. Attackers can overload servers by exploiting regex vulnerabilities in User-Agent strings.
uap-core before 0.7.3 is vulnerable to a denial of service attack due to regex vulnerabilities. Attackers can overload servers by sending crafted User-Agent strings.
Understanding CVE-2020-5243
This CVE involves a denial of service vulnerability in uap-core versions prior to 0.7.3.
What is CVE-2020-5243?
uap-core < 0.7.3 is susceptible to denial of service attacks when processing maliciously crafted User-Agent strings. The issue arises from regex vulnerabilities leading to potential server overload.
The Impact of CVE-2020-5243
- CVSS Base Score: 5.7 (Medium Severity)
- Attack Vector: Network
- Attack Complexity: Low
- Availability Impact: High
- Privileges Required: Low
- User Interaction: Required
- Scope: Unchanged
- This vulnerability allows remote attackers to disrupt services by exploiting overlapping capture groups in regexes.
Technical Details of CVE-2020-5243
This section delves into the technical aspects of the vulnerability.
Vulnerability Description
The vulnerability in uap-core < 0.7.3 enables remote attackers to launch denial of service attacks by manipulating User-Agent strings with crafted regex patterns.
Affected Systems and Versions
- Affected Product: uap-core
- Vendor: ua-parser
- Vulnerable Versions: < 0.7.3
Exploitation Mechanism
Attackers can exploit this vulnerability by sending specially crafted User-Agent strings containing malicious regex patterns, causing server overload.
Mitigation and Prevention
Protecting systems from CVE-2020-5243 requires immediate actions and long-term security practices.
Immediate Steps to Take
- Update uap-core to version 0.7.3 or newer to mitigate the vulnerability.
- Monitor and filter incoming User-Agent strings for suspicious patterns.
Long-Term Security Practices
- Regularly update software and libraries to patch known vulnerabilities.
- Implement network-level protections to mitigate denial of service attacks.
Patching and Updates
- Apply patches provided by the vendor promptly to address the vulnerability and enhance system security.