CVE-2021-31866

mediumpriority · track · 21EPSS 0.012 · 69 %ileEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.23% (69th) EPSS

CVSS 5 · medium

Is it mine?

12 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

EPSS · scored 2026-10-28

Redmine before 4.0.9 and 4.1.x before 4.1.3 allows an attacker to learn the values of internal authentication keys by observing timing differences in string comparison operations within SysController and MailHandlerController.

cvss

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

5.3

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.05mediumAV:N/AC:L/Au:N/C:P/I:N/A:Nprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:Nprimary · NVD / NIST USexploitability 3.9 · impact 1.4

v3.15.3mediumAV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:Nsecondary · FSTEC (BDU) RU

v3.14.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-203USprimaryCWE-203US

affected products (12)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
Jean-Philippe Lang Redmine≤ 4.0.9fstec_bduRU
Jean-Philippe Lang Redmine4.1.0 → 4.1.3fstec_bduRU
АО «Концерн ВНИИНС» ОС ОН «Стрелец»≤ 16.01.2023fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 1.6 «Смоленск»fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition для «Эльбрус»≤ 8.1 «Ленинград»fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 9fstec_bduRU
debian debian linux= 9.0nvdUScpe:2.3:o:debian:debian_linux:*:*:*:*:*:*:*:*
redmine redmine< 4.0.9nvdUScpe:2.3:a:redmine:redmine:*:*:*:*:*:*:*:*
redmine redmine4.1.0 → 4.1.3nvdUScpe:2.3:a:redmine:redmine:*:*:*:*:*:*:*:*
Bitnami redmine< 4.0.9osvUSpkg:bitnami/redmine
Bitnami redmine4.1.0 → 4.1.3osvUSpkg:bitnami/redmine

advisories (1)

Vendor and ecosystem advisories describing this.

BIT-redmine-2021-318662024-03-06vendor · osvUS
Redmine before 4.0.9 and 4.1.x before 4.1.3 allows an attacker to learn the values of internal authentication keys by observing timing differences in string comparison operations within SysController and MailHandlerController.

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 osv NVD CVE.org MITRE

published 2021-04-28modified 2026-06-17

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+882 more

references (12)

External citations — patches, advisories, analysis.

scry

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