Staging Environment: Content and features may be unstable or change without notice.
Search for vulnerabilities
Vulnerability details: VCID-12x8-jxdf-jqdz
Vulnerability ID VCID-12x8-jxdf-jqdz
Aliases CVE-2021-22881
GHSA-8877-prq4-9xfw
Summary Actionpack Open Redirect Vulnerability The Host Authorization middleware in Action Pack before 6.1.2.1, 6.0.3.5 suffers from an open redirect vulnerability. Specially crafted `Host` headers in combination with certain "allowed host" formats can cause the Host Authorization middleware in Action Pack to redirect users to a malicious website.
Status Published
Exploitability 0.5
Weighted Severity 6.2
Risk 3.1
Affected and Fixed Packages Package Details
Weaknesses (3)
CWE-601 URL Redirection to Untrusted Site ('Open Redirect')
CWE-1035 OWASP Top Ten 2017 Category A9 - Using Components with Known Vulnerabilities
CWE-937 OWASP Top Ten 2013 Category A9 - Using Components with Known Vulnerabilities
System Score Found at
cvssv3 6.1 https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2021-22881.json
epss 0.15453 https://api.first.org/data/v1/epss?cve=CVE-2021-22881
epss 0.15453 https://api.first.org/data/v1/epss?cve=CVE-2021-22881
epss 0.15453 https://api.first.org/data/v1/epss?cve=CVE-2021-22881
epss 0.15453 https://api.first.org/data/v1/epss?cve=CVE-2021-22881
epss 0.15453 https://api.first.org/data/v1/epss?cve=CVE-2021-22881
epss 0.15453 https://api.first.org/data/v1/epss?cve=CVE-2021-22881
epss 0.15453 https://api.first.org/data/v1/epss?cve=CVE-2021-22881
epss 0.15453 https://api.first.org/data/v1/epss?cve=CVE-2021-22881
cvssv3.1 6.1 https://benjamin-bouchet.com/cve-2021-22881-faille-de-securite-dans-le-middleware-hostauthorization
generic_textual MODERATE https://benjamin-bouchet.com/cve-2021-22881-faille-de-securite-dans-le-middleware-hostauthorization
cvssv3.1 6.1 https://discuss.rubyonrails.org/t/cve-2021-22881-possible-open-redirect-in-host-authorization-middleware/77130
generic_textual MODERATE https://discuss.rubyonrails.org/t/cve-2021-22881-possible-open-redirect-in-host-authorization-middleware/77130
cvssv3.1 6.1 https://ftp.suse.com/pub/projects/security/yaml/suse-cvss-scores.yaml
cvssv3.1_qr MODERATE https://github.com/advisories/GHSA-8877-prq4-9xfw
cvssv3.1 6.1 https://github.com/rails/rails
generic_textual MODERATE https://github.com/rails/rails
cvssv3.1 6.1 https://github.com/rails/rails/blob/v6.1.2.1/actionpack/CHANGELOG.md
generic_textual MODERATE https://github.com/rails/rails/blob/v6.1.2.1/actionpack/CHANGELOG.md
cvssv3.1 6.1 https://github.com/rails/rails/commit/b5de7b3a4787d8a55aaad39f477c16e3af65e444
generic_textual MODERATE https://github.com/rails/rails/commit/b5de7b3a4787d8a55aaad39f477c16e3af65e444
cvssv3.1 6.1 https://github.com/rubysec/ruby-advisory-db/blob/master/gems/actionpack/CVE-2021-22881.yml
generic_textual MODERATE https://github.com/rubysec/ruby-advisory-db/blob/master/gems/actionpack/CVE-2021-22881.yml
cvssv3 6.1 https://groups.google.com/g/rubyonrails-security/c/zN_3qA26l6E
cvssv3.1 6.1 https://groups.google.com/g/rubyonrails-security/c/zN_3qA26l6E
generic_textual MODERATE https://groups.google.com/g/rubyonrails-security/c/zN_3qA26l6E
cvssv3.1 6.1 https://hackerone.com/reports/1047447
generic_textual MODERATE https://hackerone.com/reports/1047447
cvssv3.1 6.1 https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/XQ3NS4IBYE2I3MVMGAHFZBZBIZGHXHT3
generic_textual MODERATE https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/XQ3NS4IBYE2I3MVMGAHFZBZBIZGHXHT3
cvssv3.1 6.1 https://nvd.nist.gov/vuln/detail/CVE-2021-22881
generic_textual MODERATE https://nvd.nist.gov/vuln/detail/CVE-2021-22881
cvssv3.1 6.1 https://rubygems.org/gems/actionpack
generic_textual MODERATE https://rubygems.org/gems/actionpack
cvssv3.1 6.1 http://www.openwall.com/lists/oss-security/2021/05/05/2
generic_textual MODERATE http://www.openwall.com/lists/oss-security/2021/05/05/2
cvssv3.1 6.1 http://www.openwall.com/lists/oss-security/2021/08/20/1
generic_textual MODERATE http://www.openwall.com/lists/oss-security/2021/08/20/1
cvssv3.1 6.1 http://www.openwall.com/lists/oss-security/2021/12/14/5
generic_textual MODERATE http://www.openwall.com/lists/oss-security/2021/12/14/5
Reference id Reference type URL
https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2021-22881.json
https://api.first.org/data/v1/epss?cve=CVE-2021-22881
https://benjamin-bouchet.com/cve-2021-22881-faille-de-securite-dans-le-middleware-hostauthorization
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-22881
https://discuss.rubyonrails.org/t/cve-2021-22881-possible-open-redirect-in-host-authorization-middleware/77130
https://ftp.suse.com/pub/projects/security/yaml/suse-cvss-scores.yaml
https://github.com/rails/rails
https://github.com/rails/rails/blob/v6.1.2.1/actionpack/CHANGELOG.md
https://github.com/rails/rails/commit/b5de7b3a4787d8a55aaad39f477c16e3af65e444
https://github.com/rubysec/ruby-advisory-db/blob/master/gems/actionpack/CVE-2021-22881.yml
https://groups.google.com/g/rubyonrails-security/c/zN_3qA26l6E
https://hackerone.com/reports/1047447
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/XQ3NS4IBYE2I3MVMGAHFZBZBIZGHXHT3
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/XQ3NS4IBYE2I3MVMGAHFZBZBIZGHXHT3/
https://nvd.nist.gov/vuln/detail/CVE-2021-22881
https://rubygems.org/gems/actionpack
http://www.openwall.com/lists/oss-security/2021/05/05/2
http://www.openwall.com/lists/oss-security/2021/08/20/1
http://www.openwall.com/lists/oss-security/2021/12/14/5
1930211 https://bugzilla.redhat.com/show_bug.cgi?id=1930211
CVE-2021-22881-FAILLE-DE-SECURITE-DANS-LE-MIDDLEWARE-HOSTAUTHORIZATION https://benjamin-bouchet.com/cve-2021-22881-faille-de-securite-dans-le-middleware-hostauthorization/
GHSA-8877-prq4-9xfw https://github.com/advisories/GHSA-8877-prq4-9xfw
No exploits are available.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Found at https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2021-22881.json
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Found at https://benjamin-bouchet.com/cve-2021-22881-faille-de-securite-dans-le-middleware-hostauthorization
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Found at https://discuss.rubyonrails.org/t/cve-2021-22881-possible-open-redirect-in-host-authorization-middleware/77130
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:L Found at https://ftp.suse.com/pub/projects/security/yaml/suse-cvss-scores.yaml
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Found at https://github.com/rails/rails
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Found at https://github.com/rails/rails/blob/v6.1.2.1/actionpack/CHANGELOG.md
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Found at https://github.com/rails/rails/commit/b5de7b3a4787d8a55aaad39f477c16e3af65e444
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Found at https://github.com/rubysec/ruby-advisory-db/blob/master/gems/actionpack/CVE-2021-22881.yml
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Found at https://groups.google.com/g/rubyonrails-security/c/zN_3qA26l6E
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Found at https://hackerone.com/reports/1047447
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Found at https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/XQ3NS4IBYE2I3MVMGAHFZBZBIZGHXHT3
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Found at https://nvd.nist.gov/vuln/detail/CVE-2021-22881
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Found at https://rubygems.org/gems/actionpack
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Found at http://www.openwall.com/lists/oss-security/2021/05/05/2
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Found at http://www.openwall.com/lists/oss-security/2021/08/20/1
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Found at http://www.openwall.com/lists/oss-security/2021/12/14/5
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Exploit Prediction Scoring System (EPSS)
Percentile 0.94619
EPSS Score 0.15453
Published At April 1, 2026, 12:55 p.m.
Date Actor Action Source VulnerableCode Version
2026-04-01T13:01:56.355796+00:00 GithubOSV Importer Import https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2021/03/GHSA-8877-prq4-9xfw/GHSA-8877-prq4-9xfw.json 38.0.0