CVE-2021-27710

highpriority · track · 42EPSS 0.079 · 95 %ileEUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

7.90% (95th) EPSS

CVSS 10 · high

Is it mine?

3 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-28

Command Injection in TOTOLINK X5000R router with firmware v9.1.0u.6118_B20201102, and TOTOLINK A720R router with firmware v4.1.5cu.470_B20200911 allows remote attackers to execute arbitrary OS commands by sending a modified HTTP request. This occurs because the function executes glibc's system function with untrusted input. In the function, "ip" parameter is directly passed to the attacker, allowing them to control the "ip" field to attack the OS.

cvss

Technical severity, 0–10. One row per scoring source.

10.0

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 9–10

v2.010highAV:N/AC:L/Au:N/C:C/I:C/A:Cprimary · NVD / NIST USexploitability 10 · impact 10

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 5.9

v3.19criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-78USprimary

affected products (3)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
totolink a720r firmware= 4.1.5cu.470_b20200911nvdUScpe:2.3:o:totolink:a720r_firmware:*:*:*:*:*:*:*:*
totolink x5000r firmware= 9.1.0u.6118_b20201102nvdUScpe:2.3:o:totolink:x5000r_firmware:*:*:*:*:*:*:*:*

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2021-04-14modified 2026-06-17

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references (7)

External citations — patches, advisories, analysis.

https://hackmd.io/Hy3oVgtcQiuqAtv9FdylHw cnnvd
https://hackmd.io/KjXzQdjDRjOuRjoZZXQo_A cnnvd
https://nvd.nist.gov/vuln/detail/CVE-2021-27710 cnnvd
https://hackmd.io/Hy3oVgtcQiuqAtv9FdylHw enisa_euvd
https://hackmd.io/KjXzQdjDRjOuRjoZZXQo_A enisa_euvd
https://hackmd.io/Hy3oVgtcQiuqAtv9FdylHwExploitThird Party Advisorynvd
https://hackmd.io/KjXzQdjDRjOuRjoZZXQo_AExploitThird Party Advisorynvd

scry

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