How severe is CVE-2021-41653?

CVE-2021-41653 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-41653 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 77% (100th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-41653?

CVE-2021-41653 affects Tp-link Tl-wr840n Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-41653?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2021-41653 published?

CVE-2021-41653 was published on 2021-11-13 and last updated on 2026-07-05.

CVE-2021-41653

CVE-2021-41653 is a critical-severity vulnerability in Tp-link Tl-wr840n Firmware with a CVSS 3.x base score of 9.8. Its EPSS exploit-prediction score of 77% places it in the 100th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-94.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 10.0
EPSS exploit prediction: 77% (100th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-94
Affected product: Tp-link Tl-wr840n Firmware
Published: 2021-11-13
Last modified: 2026-07-05

Description

The PING function on the TP-Link TL-WR840N EU v5 router with firmware through TL-WR840N(EU)_V5_171211 is vulnerable to remote code execution via a crafted payload in an IP address input field.

Frequently asked questions

What is CVE-2021-41653?: The PING function on the TP-Link TL-WR840N EU v5 router with firmware through TL-WR840N(EU)_V5_171211 is vulnerable to remote code execution via a crafted payload in an IP address input field.
How severe is CVE-2021-41653?: CVE-2021-41653 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-41653 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 77% (100th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-41653?: CVE-2021-41653 affects Tp-link Tl-wr840n Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-41653?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-41653 published?: CVE-2021-41653 was published on 2021-11-13 and last updated on 2026-07-05.

References

Affected products (1)

cpe:2.3:o:tp-link:tl-wr840n_firmware:*:*:*:*:*:*:*:*

More vulnerabilities in Tp-link Tl-wr840n Firmware

CVE-2022-25064 — Critical (CVSS 9.8): TP-LINK TL-WR840N(ES)_V6.20_180709 was discovered to contain a remote code execution (RCE) vulnerability via the…
CVE-2022-25061 — Critical (CVSS 9.8): TP-LINK TL-WR840N(ES)_V6.20_180709 was discovered to contain a command injection vulnerability via the component…
CVE-2022-25060 — Critical (CVSS 9.8): TP-LINK TL-WR840N(ES)_V6.20_180709 was discovered to contain a command injection vulnerability via the component…
CVE-2020-36178 — Critical (CVSS 9.8): oal_ipt_addBridgeIsolationRules on TP-Link TL-WR840N 6_EU_0.9.1_4.16 devices allows OS command injection because a raw…
CVE-2018-11714 — Critical (CVSS 9.8): An issue was discovered on TP-Link TL-WR840N v5 00000005 0.9.1 3.16 v0001.0 Build 170608 Rel.58696n and TL-WR841N v13…
CVE-2023-39471 — High (CVSS 8.8): TP-Link TL-WR841N ated_tp Command Injection Remote Code Execution Vulnerability. This vulnerability allows…

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