High severity · published Jan 1, 2022
CVE-2021-41819
CGI::Cookie.parse in Ruby through 2.6.8 mishandles security prefixes in cookie names
7.5
CVSS
3.2%
EPSS
No
On KEV
Description
CGI::Cookie.parse in Ruby through 2.6.8 mishandles security prefixes in cookie names. This also affects the CGI gem through 0.3.0 for Ruby.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)3.2% · higher than 88% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CG
Cgi · Ruby-lang
0.1.0; 0.2.0; 0.3.0 · source: NVD
DL
Debian Linux · Debian
9.0; 10.0; 11.0 · source: NVD
EL
Enterprise Linux · Redhat
8.0 · source: NVD
FA
Factory · Opensuse
All versions, or not specified · source: NVD
FE
Fedora · Fedoraproject
34; 35 · source: NVD
LE
Leap · Opensuse
15.2 · source: NVD
LE
Linux Enterprise · Suse
11.0; 12.0; 15.0 · source: NVD
RU
Ruby · Ruby-lang
through 2.6.8; 2.7.0 before 2.7.5; 3.0.0 before 3.0.3 · source: NVD
SC
Software Collections · Redhat
All versions, or not specified · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-41819
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-41819
Permissions Required
https://hackerone.com/reports/910552
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IUXQCH6FRKANCVZO2Q7D2SQX33FP3KWN/
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UTOJGS5IEFDK3UOO7IY4OTTFGHGLSWZF/
security.gentoo.org
https://security.gentoo.org/glsa/202401-27
Third Party Advisory
https://security.netapp.com/advisory/ntap-20220121-0003/
Exploit
https://www.ruby-lang.org/en/news/2021/11/24/cookie-prefix-spoofing-in-cgi-cookie-parse-cve-2021-41819/
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