CVE-2021-27104

highpriority · act · 90OT risk · criticalKEV · exploitedEPSS 0.567 · 99 %ileEURUUS

grimoire priorityP0 · Act now

Exploitable?

Yes · in the wild

CISA KEV

Likely / severe?

56.7% (99th) EPSS

CVSS 10 · high

Is it mine?

3 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

added 2021-11-03remediate by 2021-11-17

required action Apply updates per vendor instructions.

EPSS · scored 2026-10-27

Accellion FTA OS Command Injection Vulnerability

Accellion FTA 9_12_370 and earlier is affected by OS command execution via a crafted POST request to various admin endpoints. The fixed version is FTA_9_12_380 and later.

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 · 9.8–10

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

v3.19.8criticalAV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · ENISA EU

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

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Hsecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: active · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-78USprimaryCWE-78US

ATT&CK techniques

ATT&CK techniques this enables or maps to.

affected products (3)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
Accellion Inc Accellion FTA≤ 9_12_370fstec_bduRU
accellion fta≤ 9_12_370nvdUScpe:2.3:a:accellion:fta:*:*:*:*:*:*:*:*

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu nvd NVD CVE.org MITRE

published 2021-02-16modified 2026-06-17

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Zbtlink WE1326, WE357, WE5926, WE5926-WD, WE826-Q, WE826-T2, WE826-WD, WG108, and WG3526 firmware 19.1101, Zbtlink WE2426-C firmware 19.1112, Zbtlink WE5926-EC_QP firmware 20.0516,…

+7943 more

references (8)

External citations — patches, advisories, analysis.

https://github.com/accellion/CVEs/blob/main/CVE-2021-27104.txt cnnvd
https://nvd.nist.gov/vuln/detail/CVE-2021-27104 cnnvd
https://www.accellion.com/products/fta/cnnvd
https://github.com/accellion/CVEs/blob/main/CVE-2021-27104.txt enisa_euvd
https://www.accellion.com/products/fta/enisa_euvd
https://github.com/accellion/CVEs/blob/main/CVE-2021-27104.txtBroken LinkThird Party Advisorynvd
https://www.accellion.com/products/fta/ProductVendor Advisorynvd
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-27104US Government Resourcenvd

scry

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