CVE-2021-21289

highpriority · track · 34EPSS 0.035 · 89 %ileEUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
3.51% (89th) EPSS
CVSS 7.6 · high
Is it mine?
6 products
Check your exposure
Who says so?
4 sources
cnnvd · enisa_euvd · nvd · osv

EPSS · scored 2026-10-27

Mechanize is an open-source ruby library that makes automated web interaction easy. In Mechanize from version 2.0.0 and before version 2.7.7 there is a command injection vulnerability. Affected versions of mechanize allow for OS commands to be injected using several classes' methods which implicitly use Ruby's Kernel.open method. Exploitation is possible only if untrusted input is used as a local filename and passed to any of these calls: Mechanize::CookieJar#load, Mechanize::CookieJar#save_as, Mechanize#download, Mechanize::Download#save, Mechanize::File#save, and Mechanize::FileResponse#read_body. This is fixed in version 2.7.7.

01

cvss

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

8.3
010

base score 0–10 · higher = more severe · hover a vector to decode

v2.07.6highAV:N/AC:H/Au:N/C:C/I:C/A:Cprimary · NVD / NIST USexploitability 4.9 · impact 10
v3.18.3highCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 1.6 · impact 6
v3.17.4highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:Nsecondary · ENISA EU
v3.17.4highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:Nsecondary · security-advisories@github.comexploitability 2.8 · impact 4
v3.17.4highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:Nsecondary · OSV
v3.17.6highCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)
02

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-78USprimaryCWE-78US
03

affected products (6)

Products and version ranges known to be affected.

04

advisories (1)

Vendor and ecosystem advisories describing this.

  • GHSA-qrqm-fpv6-6r8gCommand Injection Vulnerability in Mechanize2021-02-02ghsa · osvUS

    This security advisory has been created for public disclosure of a Command Injection vulnerability that was responsibly reported by @kyoshidajp (Katsuhiko YOSHIDA). ### Impact Mechanize `>= v2.0`, `< v2.7.7` allows for OS commands to be injected using several classes' methods which implicitly use Ruby's `Kernel.open` method. Exploitation is possible only if untrusted input is used as a local filename and passed to any of these calls: - `Mechanize::CookieJar#load`: since v2.0 (see 208e3ed) - `Mechanize::CookieJar#save_as`: since v2.0 (see 5b776a4) - `Mechanize#download`: since v2.2 (see dc91667) - `Mechanize::Download#save` and `#save!` since v2.1 (see 98b2f51, bd62ff0) - `Mechanize::File#save` and `#save_as`: since v2.1 (see 2bf7519) - `Mechanize::FileResponse#read_body`: since v2.0 (see 01039f5) ### Patches These vulnerabilities are patched in Mechanize v2.7.7. ### Workarounds No workarounds are available. We recommend upgrading to v2.7.7 or later. ### References See https://docs.rubocop.org/rubocop/cops_security.html#securityopen for background on why `Kernel.open` should not be used with untrusted input. ### For more information If you have any questions or comments about this advisory, please open an issue in [sparklemotion/mechanize](https://github.com/sparklemotion/mechanize/issues/new).

05

also known as (3)

Other names and identifiers for this entity.

06

sources

Which sources assert this record, and when.

cnnvdenisa_euvdnvdosvNVDCVE.orgMITRE
published 2021-02-02modified 2026-06-17
08

references (28)

External citations — patches, advisories, analysis.

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