Subversion's mod_dontdothat module and HTTP clients 1.4.0 through 1.8.16, and 1.9.0 through 1.9.4 are vulnerable to a denial-of-service attack caused by exponential XML entity expansion. The attack can cause the targeted process to consume an excessive amount of CPU resources or memory.
The MITRE CVE dictionary describes this issue as:
Find out more about CVE-2016-8734 from the MITRE CVE dictionary dictionary and NIST NVD.
NOTE: The following CVSS v2 metrics and score provided are preliminary and subject to review.
| Base Score | 3.5 |
|---|---|
| Base Metrics | AV:N/AC:M/Au:S/C:N/I:N/A:P |
| Access Vector | Network |
| Access Complexity | Medium |
| Authentication | Single |
| Confidentiality Impact | None |
| Integrity Impact | None |
| Availability Impact | Partial |
NOTE: The following CVSS v3 metrics and score provided are preliminary and subject to review.
| CVSS3 Base Score | 4.4 |
|---|---|
| CVSS3 Base Metrics | CVSS:3.0/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H |
| Attack Vector | Network |
| Attack Complexity | High |
| Privileges Required | High |
| User Interaction | None |
| Scope | Unchanged |
| Confidentiality | None |
| Integrity Impact | None |
| Availability Impact | High |
Find out more about Red Hat support for the Common Vulnerability Scoring System (CVSS).
| Platform | Package | State |
|---|---|---|
| Red Hat Enterprise Linux 7 | subversion | Will not fix |
| Red Hat Enterprise Linux 6 | subversion | Not affected |
| Red Hat Enterprise Linux 5 | subversion | Not affected |
Only Apache+Subversion servers that have the "DontDoThatConfigFile" configuration option present are affected by this flaw. This option is not enabled in default httpd or mod_dav_svn configuration as shipped with Red Hat Enterprise Linux.
Vulmon