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CVE-2018-19989: D Link Dir 822 Firmware: Command injection
CVE-2018-19989 is rated critical with a CVSS v3.0 base score of 9.8 and NVD lists 2 affected products, including D Link Dir 822 Firmware. 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
In the /HNAP1/SetQoSSettings message, the uplink parameter is vulnerable, and the vulnerability affects D-Link DIR-822 Rev.B 202KRb06 and DIR-822 Rev.C 3.10B06 devices. In the SetQoSSettings.php source code, the uplink parameter is saved in the /bwc/entry:1/bandwidth and /bwc/entry:2/bandwidth internal configuration memory without any regex checking. And in the bwc_tc_spq_start, bwc_tc_wfq_start, and bwc_tc_adb_start functions of the bwcsvcs.php source code, the data in /bwc/entry:1/bandwidth and /bwc/entry:2/bandwidth is used with the tc command without any regex checking. A vulnerable /HNAP1/SetQoSSettings XML message could have shell metacharacters in the uplink element such as the `telnetd` string.
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-78: Improper Neutralization of Special Elements used in an OS Command
The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command before it is sent to a downstream component.
Affected products
- D Link Dir 822 Firmware: 202krb06
- D-Link Dir 822 Firmware: 3.10b06