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TI-2020-18498 Aliases CVE-2020-36178GHSA-qqg6-4j54-68gr

oal_ipt_addBridgeIsolationRules on TP-Link TL-WR840N 6_EU_0.9.1_4.16 devices allows OS…

Priority MEDIUM 54CWE-78Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-78.

Summary

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.

Why it matters now

EPSS 0.09816 95th percentileScored 2026-11-07
Public exploit Yes 2 exploit referencesTagged by NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:o:tp-link:tl-wr840n_firmware:6_eu_0.9.1_4.16:*:*:*:*:*:*:*6_eu_0.9.1_4.16VulnerableTP-Link
cpe:2.3:h:tp-link:tl-wr840n:-:*:*:*:*:*:*:*not specified by NVDRunning onTP-Link
  • cpe:2.3:o:tp-link:tl-wr840n_firmware:6_eu_0.9.1_4.16:*:*:*:*:*:*:* Versions 6_eu_0.9.1_4.16 Vulnerable ·TP-Link
  • cpe:2.3:h:tp-link:tl-wr840n:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·TP-Link

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2020-36178
  2. 2026-10-03 Alias added: GHSA-qqg6-4j54-68gr

References

Exploit 2

Advisory 1

  • TI-2023-27456 Authentication bypass by spoofing in TP-Link TL-WR841N KEVCVSS 3.1MEDIUM 6.5
  • TI-2021-18357 The PING function on the TP-Link TL-WR840N EU v5 router with firmware through… CVSS 3.1CRITICAL 9.8
  • TI-2018-08378 An issue was discovered on TP-Link TL-WR840N v5 00000005 0.9.1 3.16 v0001.0 Build 170608… CVSS 3.0CRITICAL 9.8
  • TI-2022-08817 TP-LINK TL-WR840N(ES)_V6.20_180709 was discovered to contain a command injection… CVSS 3.1CRITICAL 9.8
  • TI-2026-02790 Authenticated Command Injection on TP-Link TL-WR802N, TL-WR841N and TL-WR840N CVSS 4.0HIGH 8.5
  • TI-2022-08816 TP-LINK TL-WR840N(ES)_V6.20_180709 was discovered to contain a command injection… CVSS 3.1CRITICAL 9.8
See all 21 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences