Home
» Security vulnerabilities
» CVE-2021-27764
Cookie without HTTPONLY flag set. NUMBER cookie(s) was set without Secure or HTTPOnly flags. The images show the cookie with the missing flag. (WebUI)
NVD Status: Modified ,CVE State: published
Threat Intelligence & Risk Assessment for CVE-2021-27764
Conclusion & alert: CVE-2021-27764 is rated Moderate Risk (43.7/100) : CVSS High severity, with low exploitation likelihood (EPSS 0.51%). Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
Exploit prediction scoring system (EPSS) score for CVE-2021-27764
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
#
Date
Old EPSS score
New EPSS score
Delta (New - Old)
1
2026-06-15
0.07%
0.51%
+0.43%
2
2025-03-17
0.15%
0.07%
-0.08%
3
2023-11-27
—
0.15%
—
Full EPSS history
(5 records total)
Common vulnerability scoring system (CVSS) metrics for CVE-2021-27764
CVSS metrics for this CVE.
Base score
Version
Severity
Vector
Exploitability
Impact
Score source
7.4
3.1
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N
Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
2.8
4.0
[email protected]
6.5
3.1
MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
2.8
3.6
[email protected]
4.3
2.0
MEDIUM
AV:N/AC:M/Au:N/C:P/I:N/A:N
Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
8.6
2.9
[email protected]
Weakness enumeration for CVE-2021-27764
Affected software / configurations for CVE-2021-27764
Vendor
Product
Version
Raw CPE
hcltech
bigfix_webui
—
cpe:2.3:a:hcltech:bigfix_webui:-:*:*:*:*:*:*:*
References for CVE-2021-27764
cvelogic
Threat Intelligence