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CVE-2021-26091

Quick assessment

Affected
Fortinet FortiMail
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

Fortinet FortiMail是美国飞塔（Fortinet）公司的一套电子邮件安全网关产品。该产品提供电子邮件安全防护和数据保护等功能。 Fortinet FortiMail 存在安全特征问题漏洞，该漏洞源于FortiMail 基于身份加密服务的身份验证器中使用了弱伪随机数生成器。攻击者可利用该漏洞推断部分用户身份验证令牌并重置他们的凭据。

CVSS 6.9 · High EPSS 0.31% · P21

Possible ATT&CK Techniques 1 AI

T1552 · Unsecured Credentials
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I. Basic Information for CVE-2021-26091

Vulnerability Information
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Vulnerability Title
N/A
Source: CVE Program / CVE List V5
Vulnerability Description
A use of a cryptographically weak pseudo-random number generator vulnerability in the authenticator of the Identity Based Encryption service of FortiMail 6.4.0 through 6.4.4, and 6.2.0 through 6.2.7 may allow an unauthenticated attacker to infer parts of users authentication tokens and reset their credentials.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Source: CVE Program / CVE List V5
Vulnerability Type
使用具有密码学弱点缺陷的PRNG
Source: CVE Program / CVE List V5
Vulnerability Title
Fortinet FortiMail 安全特征问题特征问题漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Fortinet FortiMail是美国飞塔（Fortinet）公司的一套电子邮件安全网关产品。该产品提供电子邮件安全防护和数据保护等功能。 Fortinet FortiMail 存在安全特征问题漏洞，该漏洞源于FortiMail 基于身份加密服务的身份验证器中使用了弱伪随机数生成器。攻击者可利用该漏洞推断部分用户身份验证令牌并重置他们的凭据。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
Fortinet FortiMail 6.4.0 ~ 6.4.4 cpe:2.3:a:fortinet:fortimail:6.4.4:*:*:*:*:*:*:*

II. Public POCs for CVE-2021-26091

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III. Intelligence Information for CVE-2021-26091

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Vendor Advisories for CVE-2021-26091 (1)

Same Patch Batch · Fortinet · 2025-03-24 · 3 CVEs total

CVE-2023-25610 9.3 CRITICAL Fortinet FortiOS和FortiProxy 安全漏洞
CVE-2021-26105 6.4 MEDIUM Fortinet FortiSandbox 安全漏洞

IV. Related Vulnerabilities

Same product: FortiMail
Same vendor: Fortinet
Same weakness: CWE-338

V. Comments for CVE-2021-26091

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