CVE-2020-36178
oal_ipt_addBridgeIsolationRules on TP-Link TL-WR840N 6_EU_0.9.1_4.16 devices allows OS command...
oal_ipt_addBridgeIsolationRules on TP-Link TL-WR840N 6_EU_0.9.1_4.16 devices allows OS command injection because a raw string entered from the web interface (an IP address field) is used directly for a call to the system library function (for iptables). NOTE: oal_ipt_addBridgeIsolationRules is not the only function that calls util_execSystem.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
oal_ipt_addBridgeIsolationRules on TP-Link TL-WR840N 6_EU_0.9.1_4.16 devices allows OS command injection because a raw string entered from the web interface (an IP address field) is used directly for a call to the system library function (for iptables). NOTE: oal_ipt_addBridgeIsolationRules is not the only function that calls util_execSystem.
- Record
CVE-2020-36178- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 10.0 High
AV:N/AC:L/Au:N/C:C/I:C/A:C - Weakness
- CWE-78
- Updated
- 2026-11-02
CVE List No score
oal_ipt_addBridgeIsolationRules on TP-Link TL-WR840N 6_EU_0.9.1_4.16 devices allows OS command injection because a raw string entered from the web interface (an IP address field) is used directly for a call to the system library function (for iptables). NOTE: oal_ipt_addBridgeIsolationRules is not the only function that calls util_execSystem.
- Record
CVE-2020-36178- Updated
- 2026-11-02
EUVDEUVD-2020-23756 No score
oal_ipt_addBridgeIsolationRules on TP-Link TL-WR840N 6_EU_0.9.1_4.16 devices allows OS command injection because a raw string entered from the web interface (an IP address field) is used directly for a call to the system library function (for iptables). NOTE: oal_ipt_addBridgeIsolationRules is not the only function that calls util_execSystem.
- Record
EUVD-2020-23756- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-qqg6-4j54-68gr No score
oal_ipt_addBridgeIsolationRules on TP-Link TL-WR840N 6_EU_0.9.1_4.16 devices allows OS command...
oal_ipt_addBridgeIsolationRules on TP-Link TL-WR840N 6_EU_0.9.1_4.16 devices allows OS command injection because a raw string entered from the web interface (an IP address field) is used directly for a call to the system library function (for iptables).
- Record
GHSA-qqg6-4j54-68gr- Weakness
- CWE-78
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2020-36178 is a critical vulnerability (CVSS 9.8) in Tp-link Tl-wr840n Firmware, published January 6, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 9.82%, the 95th percentile. No source names a fixed version.