CVE-2021-31866
Status: ModifiedMedium (5.3)—
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
- Version: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
- Base score: 5.3
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 1.23%
- Percentile among all scored CVEs: 68
- Score date: 10/13/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (2)
CWEs
- CWE-203
References
- https://lists.debian.org/debian-lts-announce/2021/05/msg00013.html
- https://www.redmine.org/news/131
- https://www.redmine.org/projects/redmine/wiki/Security_Advisories
- https://lists.debian.org/debian-lts-announce/2021/05/msg00013.html
- https://www.redmine.org/news/131
- https://www.redmine.org/projects/redmine/wiki/Security_Advisories
Raw JSON (NVD)
Show
{
"id": "CVE-2021-31866",
"cveTags": [],
"metrics": {
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"vectorString": "AV:N/AC:L/Au:N/C:P/I:N/A:N",
"authentication": "NONE",
"integrityImpact": "NONE",
"accessComplexity": "LOW",
"availabilityImpact": "NONE",
"confidentialityImpact": "PARTIAL"
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"affected": [
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"published": "2021-04-28T07:15:07.663",
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"description": [
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"descriptions": [
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"value": "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."
},
{
"lang": "es",
"value": "Redmine versiones anteriores a 4.0.9 y versiones 4.1.x anteriores a 4.1.3, permite a un atacante aprender los valores de las claves de autenticación internas al observar las diferencias de tiempo en las operaciones de comparación de cadenas dentro de las funciones SysController y MailHandlerController"
}
],
"lastModified": "2026-06-17T03:52:22.387",
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