CVE-2022-29218Public exploitNetwork attack vector

Malicious package substitution via premature S3 write

Published May 12, 2022 · Updated Apr 22, 2025

Authorization failure in RubyGems.org allows remote authenticated users to substitute malicious files for platform-specific gems. The upload path wrote a crafted invalid gem to S3 before its database transaction completed, leaving no matching record while a primed Fastly cache retained the file. Exploitation requires an account, a guessed next version, a numeric platform suffix, and cache priming; downloads can receive attacker-controlled gem code.

CVSS severity7.7
High
EPSS probability1.25%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authorization failure in RubyGems.org allows remote authenticated users to substitute malicious files for platform-specific gems. The upload path wrote a crafted invalid gem to S3 before its database transaction completed, leaving no matching record while a primed Fastly cache retained the file. Exploitation requires an account, a guessed next version, a numeric platform suffix, and cache priming; downloads can receive attacker-controlled gem code.

The record

CVE
CVE-2022-29218
Published
May 12, 2022
Updated
Apr 22, 2025
Vendor
RubyGems
Product
RubyGems.org
Classifications
CWE-863, CWE-269, CWE-290, T1195.002
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. May 12, 2022CVE publishedPublication date reported by the CVE source.
  2. Apr 22, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=n/a

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

RubyGems · RubyGems.orgversion=n/a

Published CVSS scores

7.7GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N
5.0NIST National Vulnerability DatabaseAV:N/AC:L/Au:N/C:N/I:P/A:N
7.5NIST National Vulnerability DatabaseCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-863Incorrect Authorization
CWE-269Improper Privilege Management
CWE-290Authentication Bypass by Spoofing
T1195.002Compromise Software Supply Chain

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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