CVE-2021-28966

mediumpriority · attend · 50EPSS 0.580 · 99 %ileDEEUUS

grimoire priorityP1 · Urgent

Exploitable?

—

no known exploitation

Likely / severe?

58.0% (99th) EPSS

CVSS 5 · medium

Is it mine?

19 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · osv · cert_bund

EPSS · scored 2026-10-27

In Ruby through 3.0 on Windows, a remote attacker can submit a crafted path when a Web application handles a parameter with TmpDir.

cvss

Technical severity, 0–10. One row per scoring source.

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5

v2.05mediumAV:N/AC:L/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:Nprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:Nsecondary · OSV

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N/E:Hsecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-22USprimaryCWE-22US

affected products (19)

Products and version ranges known to be affected.

Amazon Linux 2all versionscert_bundDEcpe:/o:amazon:linux_2:-
Debian Linuxall versionscert_bundDEcpe:/o:debian:debian_linux:-
Open Source Ruby <2.7.3all versionscert_bundDE
Open Source Ruby <3.0.1all versionscert_bundDE
Oracle Linuxall versionscert_bundDEcpe:/o:oracle:linux:-
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
SUSE Linuxall versionscert_bundDEcpe:/o:suse:suse_linux:-
SUSE openSUSEall versionscert_bundDEcpe:/o:suse:opensuse:-
Ubuntu Linuxall versionscert_bundDEcpe:/o:canonical:ubuntu_linux:-
Open Source Ruby< 2.7.3cert_bundDE
Open Source Ruby< 3.0.1cert_bundDE
n/a n/a≤ n/aenisa_euvdEU
ruby-lang ruby< 2.7.3nvdUScpe:2.3:a:ruby-lang:ruby:*:*:*:*:*:*:*:*
ruby-lang ruby3.0.0 → 3.0.1nvdUScpe:2.3:a:ruby-lang:ruby:*:*:*:*:*:*:*:*
Bitnami ruby< 2.7.3osvUSpkg:bitnami/ruby
Bitnami ruby3.0.0 → 3.0.1osvUSpkg:bitnami/ruby
Bitnami ruby-min< 2.7.3osvUSpkg:bitnami/ruby-min
Bitnami ruby-min3.0.0 → 3.0.1osvUSpkg:bitnami/ruby-min
RubyGems tmpdir< 0.1.2osvUSpkg:gem/tmpdir

advisories (4)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2023-2462Ruby: Mehrere SchwachstellenDeutsch2021-04-05csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Ruby ausnutzen, um Sicherheitsvorkehrungen zu umgehen und Dateien zu manipulieren.
GHSA-46f2-3v63-3xrpTempfile on Windows path traversal vulnerability2021-05-06ghsa · osvUS
There is an unintentional directory creation vulnerability in `tmpdir` library bundled with Ruby on Windows. And there is also an unintentional file creation vulnerability in tempfile library bundled with Ruby on Windows, because it uses tmpdir internally.
BIT-ruby-2021-289662024-03-06vendor · osvUS
In Ruby through 3.0 on Windows, a remote attacker can submit a crafted path when a Web application handles a parameter with TmpDir.
BIT-ruby-min-2021-289662025-01-27vendor · osvUS
In Ruby through 3.0 on Windows, a remote attacker can submit a crafted path when a Web application handles a parameter with TmpDir.

also known as (6)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd osv cert_bund nvd NVD CVE.org MITRE

published 2021-07-30modified 2026-06-17

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+12524 more

references (9)

External citations — patches, advisories, analysis.

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