Missing Secure Flag From SSL Cookie

published 2021-10-27 5y ago modified 2026-06-17 4mo ago also EUVD-2021-21879

cvss: 3.1; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.5%; EPSS 0.5% chance of exploitation in 30 days, percentile 44%
public exploits: 0; none known

The Secure flag is not set in the SSL Cookie of Kiwi Syslog Server 9.7.2 and previous versions. The Secure attribute tells the browser to only send the cookie if the request is being sent over a secure channel such as HTTPS. This will help protect the cookie from being passed over unencrypted requests. If the application can be accessed over both HTTP, there is a potential for the cookie can be sent in clear text.

Patch / fix

fixed in 1

SolarWinds Kiwi Syslog Server 9.8

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Exploit prediction

0.52% chance of exploitation in the next 30 days, higher than 44% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.1	3.1	CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N
NVD	3.1	5.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
NVD	2.0	5.0	AV:N/AC:L/Au:N/C:P/I:N/A:N

Affected products

SolarWinds Kiwi Syslog Server

Classification

Weakness

CWE-614 Sensitive Cookie in HTTPS Session Without 'Secure' Attribute
CWE-311 Missing Encryption of Sensitive Data

References

documentation.solarwinds.com /en/success_center/kss/content/release_notes/kss_9-8_release_notes.htm
release-notes, vendor-advisory
solarwinds.com /trust-center/security-advisories/cve-2021-35236
vendor-advisory

Sources

CVE List CVE-2021-35236
NVD CVE-2021-35236

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