CVE-2021-3727 | OS Command Injection in ohmyzsh/ohmyzsh

# Vulnerability in `rand-quote` and `hitokoto` plugins **Description**: the `rand-quote` and `hitokoto` fetch quotes from quotationspage.com and hitokoto.cn respectively, do some process on them and then use `print -P` to print them. If these quotes contained the proper symbols, they could trigger command injection. Given that they're an external API, it's not possible to know if the quotes are safe to use. **Fixed in**: [72928432](https://github.com/ohmyzsh/ohmyzsh/commit/72928432). **Impacted areas**: - `rand-quote` plugin (`quote` function). - `hitokoto` plugin (`hitokoto` function).

Published: 2021-11-30 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2021-3727 is rated Moderate Risk (57.4/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.36%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-3727

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-05-26 1.65% 1.36% -0.29%
2 2025-03-30 4.12% 1.65% -2.47%
3 2025-03-29 4.12%

Full EPSS history (11 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-3727

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.6 5.9 [email protected]
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 5.9 [email protected]
7.5 2.0 HIGH
AV:N/AC:L/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
10.0 6.4 [email protected]

Weakness enumeration for CVE-2021-3727

Affected software / configurations for CVE-2021-3727

Vendor Product Version Raw CPE
planetargon oh_my_zsh < 72928432 cpe:2.3:a:planetargon:oh_my_zsh:*:*:*:*:*:*:*:*

References for CVE-2021-3727

URL Tags
https://github.com/ohmyzsh/ohmyzsh/commit/72928432 Patch Third Party Advisory
cvelogic Threat Intelligence