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CVE-2021-30151

33
FAUCET Score

CVE-2021-30151 is a Cross-Site Scripting (XSS) vulnerability affecting Sidekiq versions up to 5.1.3 and 6.x up to 6.2.0, specifically when used with Internet Explorer. The vulnerability allows an attacker to inject malicious scripts via the queue name in the live-poll feature. It carries a CVSS score of 6.1 (Medium), indicating a network-based attack requiring user interaction, with potential for low impact on confidentiality and integrity. While not listed in CISA's KEV catalog, a Nuclei template exists for detection, but there is no evidence of active exploitation, Metasploit modules, or significant community discussion.

Impacted Technologies

VendorProductVersion(s)CPE
<= 5.1.3CPE matchmatch criteria
cpe:2.3:a:contribsys:sidekiq:*:*:*:*:*:*:*:*
>= 6.0.0, <= 6.2.0CPE matchmatch criteria
cpe:2.3:a:contribsys:sidekiq:*:*:*:*:*:*:*:*
9.0CPE matchmatch criteria
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 3.1

6.1MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality Impact
LOW
Integrity Impact
LOW
Availability Impact
NONE
Exploitability Score
2.8
Impact Score
2.7
CvssVersion
3.1

Exploit Intelligence

EPSS Score
4.16%
Probability of exploitation in next 30 days
EPSS Percentile
89.8%
Percentile rank of EPSS score among Peer Group
As of 2026-07-27
Model: v2026.06.15
Nuclei: CVE-2021-30151 · Apr 10, 2021
This CVE's current EPSS score of 0.0416 is in the 95th percentile among its peer group of 26,234 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 Bluesky, 0.0 Mastodon, and 0.1 GitHub mentions.

Media Mentions

No media coverage found for this CVE.

The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Patch Available

Vendor Patches (4)

github_advisorypatch availablevia nvd_reference
View patch
redhatpatch availablevia redhat_api
Product: Red Hat Satellite 6.11 for RHEL 7Fixed in: tfm-rubygem-sidekiq-0:5.2.10-1.el7sat
View patch
rubygemspatch availablevia ghsa
Product: sidekiqFixed in: 5.2.0
rubygemspatch availablevia ghsa
Product: sidekiqFixed in: 6.2.1

Vendor Advisories (2)

redhatCVE-2021-30151Moderate

sidekiq: XSS via the queue name of the live-poll feature

Oct 8, 2021
rubygemsGHSA-grh7-935j-hg6wmedium

Cross-site Scripting in Sidekiq

Oct 6, 2021

References

github.com / mperham/sidekiq/issues/4852
ExploitIssue TrackingPatchThird Party Advisory
lists.debian.org / debian-lts-announce/2022/03/msg00015.html
Mailing ListThird Party Advisory
lists.debian.org / debian-lts-announce/2023/03/msg00011.html