CVE-2018-1000027
Publication date 29 January 2018
Last updated 25 August 2025
Ubuntu priority
Cvss 3 Severity Score
Description
The Squid Software Foundation Squid HTTP Caching Proxy version prior to version 4.0.23 contains a NULL Pointer Dereference vulnerability in HTTP Response X-Forwarded-For header processing that can result in Denial of Service to all clients of the proxy. This attack appear to be exploitable via Remote HTTP server responding with an X-Forwarded-For header to certain types of HTTP request. This vulnerability appears to have been fixed in 4.0.23 and later.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| squid3 | ||
| 18.04 LTS bionic |
Fixed 3.5.23-5ubuntu2
|
|
| 16.04 LTS xenial |
Fixed 3.5.12-1ubuntu7.5
|
|
| 14.04 LTS trusty |
Fixed 3.3.8-1ubuntu6.11
|
Patch details
| Package | Patch details |
|---|---|
| squid3 |
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score |
|
| Attack vector | Network |
| Attack complexity | Low |
| Privileges required | None |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | None |
| Integrity impact | None |
| Availability impact | High |
| Vector | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
References
Related Ubuntu Security Notices (USN)
- USN-3557-1
- Squid vulnerabilities
- 5 February 2018
- USN-4059-2
- Squid vulnerabilities
- 17 July 2019