PT-2021-4539 · Ruby On Rails+3 · Action Pack+3

Published

2021-05-01

·

Updated

2025-09-29

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CVE-2021-22904

CVSS v3.1

7.5

High

VectorAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Name of the Vulnerable Software and Affected Versions actionpack versions 4.0.0 through 6.1.3.1, 6.0.3.6, 5.2.4.5, 5.2.5 actionpack versions 6.1.3.2, 6.0.3.7, 5.2.4.6, 5.2.6 are not affected
Description The issue is related to a denial of service vulnerability in the Token Authentication logic in Action Controller due to a too permissive regular expression. Impacted code uses authenticate or request with http token or authenticate with http token for request authentication. This could allow a remote attacker to cause a denial of service.
Recommendations For actionpack versions 4.0.0 through 6.1.3.1, 6.0.3.6, 5.2.4.5, 5.2.5, upgrade to version 6.1.3.2, 6.0.3.7, 5.2.4.6, or 5.2.6. As a temporary workaround, consider applying the monkey patch to the initializer:
ruby
module ActionController::HttpAuthentication::Token
 AUTHN PAIR DELIMITERS = /(?:,|;|t)/
end

Exploit

Fix

DoS

Resource Exhaustion

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Weakness Enumeration

Related Identifiers

ALSA-2025_16880
ALT-PU-2021-2595
ALT-PU-2023-4268
ALT-PU-2024-7814
BDU:2021-05203
CVE-2021-22904
DLA-2655-1
DSA-4929-1
GHSA-7WJX-3G7J-8584
OESA-2021-1248
OPENSUSE-SU-2022_2108-1
OPENSUSE-SU-2024:11317-1
OPENSUSE-SU-2024:11318-1
OPENSUSE-SU-2024:11821-1
RHSA-2021:4702
SUSE-SU-2022:2108-1
SUSE-SU-2022_2108-1

Affected Products

Alt Linux
Astra Linux
Suse
Action Pack