CVE-2026-102937
virtualenv: Command injection via --prompt in activate.bat (batch activator)
virtualenv is a tool for creating isolated virtual python environments. Prior to 21.7.12, BatchActivator.quote() returns prompt text unchanged before activate.bat inserts it into a cmd.exe set "VAR=value" statement. An attacker who influences --prompt, VIRTUALENV_PROMPT, or the corresponding configuration value can include a double quote that closes the assignment and leaves following cmd.exe operators as executable syntax. When a user activates the generated Windows environment, the injected commands run with that user's privileges. This issue is fixed in version 21.7.12.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Passive
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
virtualenv: Command injection via --prompt in activate.bat (batch activator)
virtualenv is a tool for creating isolated virtual python environments. Prior to 21.7.12, BatchActivator.quote() returns prompt text unchanged before activate.bat inserts it into a cmd.exe set "VAR=value" statement. An attacker who influences --prompt, VIRTUALENV_PROMPT, or the corresponding configuration value can include a double quote that closes the assignment and leaves following cmd.exe operators as executable syntax. When a user activates the generated Windows environment, the injected commands run with that user's privileges. This issue is fixed in version 21.7.12.
- Record
CVE-2026-102937- CVSS 4.0
- 7.3 High
CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-78
- Updated
- 2026-11-02
EUVDEUVD-2026-89464
virtualenv is a tool for creating isolated virtual python environments. Prior to 21.7.12, BatchActivator.quote() returns prompt text unchanged before activate.bat inserts it into a cmd.exe set "VAR=value" statement. An attacker who influences --prompt, VIRTUALENV_PROMPT, or the corresponding configuration value can include a double quote that closes the assignment and leaves following cmd.exe operators as executable syntax. When a user activates the generated Windows environment, the injected commands run with that user's privileges. This issue is fixed in version 21.7.12.
- Record
EUVD-2026-89464- CVSS 4.0
- 7.3 High
CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-x78j-v8h9-3j2q
virtualenv: Command injection via --prompt in activate.bat (batch activator)
BatchActivator.quote() returned its input unchanged, the only activator with no escaping at all. --prompt, the VIRTUALENV_PROMPT environment variable, and the config file all set the prompt, and activate.bat writes it straight into @set "VAR=value". A prompt containing a double quote closes that string early, and whatever follows runs as live cmd.exe syntax:
$ virtualenv --prompt 'x" & calc & "' venv
$ venv\Scripts\activate.bat
runs calc the moment someone activates the environment. Confirmed on a real Windows runner. Anyone who templates a prompt from untrusted input (a CI job using a branch name, a wrapper script deriving an environment name from user input) hands an attacker code execution in the shell of anyone who activates the resulting venv on Windows.
Fixed in 21.7.12 by escaping the characters cmd.exe treats as live syntax inside this construct. Fix: https://github.com/pypa/virtualenv/pull/3250
- Record
GHSA-x78j-v8h9-3j2q- CVSS 4.0
- 7.3 High
CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-78
- Updated
- 2026-11-02
NVD
virtualenv is a tool for creating isolated virtual python environments. Prior to 21.7.12, BatchActivator.quote() returns prompt text unchanged before activate.bat inserts it into a cmd.exe set "VAR=value" statement. An attacker who influences --prompt, VIRTUALENV_PROMPT, or the corresponding configuration value can include a double quote that closes the assignment and leaves following cmd.exe operators as executable syntax. When a user activates the generated Windows environment, the injected commands run with that user's privileges. This issue is fixed in version 21.7.12.
- Record
CVE-2026-102937- CVSS 4.0
- 7.3 High
CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Weakness
- CWE-78
- Updated
- 2026-11-02
OSV
virtualenv: Command injection via --prompt in activate.bat (batch activator)
virtualenv is a tool for creating isolated virtual python environments. Prior to 21.7.12, BatchActivator.quote() returns prompt text unchanged before activate.bat inserts it into a cmd.exe set "VAR=value" statement. An attacker who influences --prompt, VIRTUALENV_PROMPT, or the corresponding configuration value can include a double quote that closes the assignment and leaves following cmd.exe operators as executable syntax. When a user activates the generated Windows environment, the injected commands run with that user's privileges. This issue is fixed in version 21.7.12.
- Record
CVE-2026-102937- CVSS 4.0
- 7.3 High
CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-78
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-102937
virtualenv is a tool for creating isolated virtual python environments. Prior to 21.7.12, BatchActivator.quote() returns prompt text unchanged before activate.bat inserts it into a cmd.exe set "VAR=value" statement. An attacker who influences --prompt, VIRTUALENV_PROMPT, or the corresponding configuration value can include a double quote that closes the assignment and leaves following cmd.exe operators as executable syntax. When a user activates the generated Windows environment, the injected commands run with that user's privileges. This issue is fixed in version 21.7.12.
- Record
DEBIAN-CVE-2026-102937- CVSS 4.0
- 7.3 High
CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Updated
- 2026-11-02
Show 8 moreShow less
OSVGHSA-x78j-v8h9-3j2q
virtualenv: Command injection via --prompt in activate.bat (batch activator)
BatchActivator.quote() returned its input unchanged, the only activator with no escaping at all. --prompt, the VIRTUALENV_PROMPT environment variable, and the config file all set the prompt, and activate.bat writes it straight into @set "VAR=value". A prompt containing a double quote closes that string early, and whatever follows runs as live cmd.exe syntax:
$ virtualenv --prompt 'x" & calc & "' venv
$ venv\Scripts\activate.bat
runs calc the moment someone activates the environment. Confirmed on a real Windows runner. Anyone who templates a prompt from untrusted input (a CI job using a branch name, a wrapper script deriving an environment name from user input) hands an attacker code execution in the shell of anyone who activates the resulting venv on Windows.
Fixed in 21.7.12 by escaping the characters cmd.exe treats as live syntax inside this construct. Fix: https://github.com/pypa/virtualenv/pull/3250
- Record
GHSA-x78j-v8h9-3j2q- CVSS 4.0
- 7.3 High
CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-78
- Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-102937
virtualenv is a tool for creating isolated virtual python environments. Prior to 21.7.12, BatchActivator.quote() returns prompt text unchanged before activate.bat inserts it into a cmd.exe set "VAR=value" statement. An attacker who influences --prompt, VIRTUALENV_PROMPT, or the corresponding configuration value can include a double quote that closes the assignment and leaves following cmd.exe operators as executable syntax. When a user activates the generated Windows environment, the injected commands run with that user's privileges. This issue is fixed in version 21.7.12.
- Record
UBUNTU-CVE-2026-102937- CVSS 4.0
- 7.3 High
CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - Updated
- 2026-11-02
OSVAZL-105648 No score
CVE-2026-102937 affecting package python-pip 24.2-10
virtualenv is a tool for creating isolated virtual python environments. Prior to 21.7.12, BatchActivator.quote() returns prompt text unchanged before activate.bat inserts it into a cmd.exe set "VAR=value" statement. An attacker who influences --prompt, VIRTUALENV_PROMPT, or the corresponding configuration value can include a double quote that closes the assignment and leaves following cmd.exe operators as executable syntax. When a user activates the generated Windows environment, the injected commands run with that user's privileges. This issue is fixed in version 21.7.12.
- Record
AZL-105648- Updated
- 2026-11-02
OSVAZL-105666 No score
CVE-2026-102937 affecting package python-virtualenv 20.36.1-6
virtualenv is a tool for creating isolated virtual python environments. Prior to 21.7.12, BatchActivator.quote() returns prompt text unchanged before activate.bat inserts it into a cmd.exe set "VAR=value" statement. An attacker who influences --prompt, VIRTUALENV_PROMPT, or the corresponding configuration value can include a double quote that closes the assignment and leaves following cmd.exe operators as executable syntax. When a user activates the generated Windows environment, the injected commands run with that user's privileges. This issue is fixed in version 21.7.12.
- Record
AZL-105666- Updated
- 2026-11-02
OSVBIT-virtualenv-2026-102937 No score
virtualenv: Command injection via --prompt in activate.bat (batch activator)
virtualenv is a tool for creating isolated virtual python environments. Prior to 21.7.12, BatchActivator.quote() returns prompt text unchanged before activate.bat inserts it into a cmd.exe set "VAR=value" statement. An attacker who influences --prompt, VIRTUALENV_PROMPT, or the corresponding configuration value can include a double quote that closes the assignment and leaves following cmd.exe operators as executable syntax. When a user activates the generated Windows environment, the injected commands run with that user's privileges. This issue is fixed in version 21.7.12.
- Record
BIT-virtualenv-2026-102937- Updated
- 2026-11-02
OSVCLSA-2026-1791452380 No score
TuxCare security update for virtualenv (4 CVEs)
TuxCare rebuilt virtualenv to address 4 CVEs. Fixed in 20.39.1.post2+tuxcare.
- Record
CLSA-2026-1791452380- Updated
- 2026-11-02
OSVPYSEC-2026-4014 No score
Command injection via --prompt in activate.bat (batch activator)
BatchActivator.quote() returned its input unchanged, the only activator with
no escaping at all. --prompt, the VIRTUALENV_PROMPT environment variable,
and the config file all set the prompt, and activate.bat writes it straight
into @set "VAR=value". A prompt containing a double quote closes that string
early, and whatever follows runs as live cmd.exe syntax. For example, a venv
created with --prompt 'x" & calc & "' runs calc the moment someone runs
activate.bat.
Anyone who templates a prompt from untrusted input (a CI job using a branch name, a wrapper script deriving an environment name from user input) hands an attacker code execution in the shell of anyone who activates the resulting venv on Windows.
Fixed in 21.7.12 by escaping the characters cmd.exe treats as live syntax inside this construct.
- Record
PYSEC-2026-4014- Updated
- 2026-11-02
OSVROOT-APP-PYPI-CVE-2026-102937 No score
CVE-2026-102937 in virtualenv - Patched by Root
Root has patched CVE-2026-102937 in the virtualenv package for Root:PyPI. Multiple fixed versions available.
- Record
ROOT-APP-PYPI-CVE-2026-102937- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
virtualenvPyPI |
through 21.7.11 | 21.7.12 |
python-pipAzure Linux:3 |
through 24.2-10 | None known |
python-virtualenvAzure Linux:3 |
through 20.36.1-6 | None known |
virtualenvBitnami |
before 21.7.12 | 21.7.12 |
virtualenvTuxCare:PyPI From an advisory covering 4 CVEs |
20.39.1 up to 20.39.1.post2+tuxcare, plus listed versions 20.39.1.post1+tuxcare |
20.39.1.post2+tuxcare |
python-virtualenvDebian:12 |
All versions, plus listed versions 20.17.1+ds-120.19.0+ds-120.21.0+ds-120.23.0+ds-120.23.0+ds-2 Show 28 moreShow less20.24.1+ds-120.24.6+ds-120.24.6+ds-220.25.0+ds-120.25.0+ds-220.25.1+ds-120.26.1+ds-120.26.2+ds-120.26.6+ds-120.27.0+ds-120.28.0+ds-120.29.1+ds-120.29.3+ds-120.30.0+ds-120.30.0+ds-220.30.0+ds-320.31.2+ds-120.33.1+ds-120.34.0+ds-120.35.3+ds-120.35.4+ds-120.36.1+ds-120.38.0+ds-121.2.0+ds-121.2.4+ds-121.3.1+ds-121.4.1+ds-121.5.1+ds-1 |
None known |
python-virtualenvDebian:13 |
All versions, plus listed versions 20.31.2+ds-120.31.2+ds-1+deb13u120.33.1+ds-120.34.0+ds-120.35.3+ds-1 Show 8 moreShow less20.35.4+ds-120.36.1+ds-120.38.0+ds-121.2.0+ds-121.2.4+ds-121.3.1+ds-121.4.1+ds-121.5.1+ds-1 |
None known |
python-virtualenvDebian:14 |
All versions, plus listed versions 20.31.2+ds-120.33.1+ds-120.34.0+ds-120.35.3+ds-120.35.4+ds-1 Show 7 moreShow less20.36.1+ds-120.38.0+ds-121.2.0+ds-121.2.4+ds-121.3.1+ds-121.4.1+ds-121.5.1+ds-1 |
None known |
virtualenvPyPI |
before 21.7.12, plus listed versions 0.80.8.10.8.20.8.30.8.4 Show 45 moreShow less0.90.9.10.9.21.01.11.101.10.11.111.11.11.11.21.11.31.11.41.11.51.11.61.21.31.3.11.3.21.3.31.3.41.41.4.11.4.21.4.31.4.41.4.51.4.61.4.71.4.81.4.91.4rc11.51.5.11.5.21.61.6.11.6.21.6.31.6.41.71.7.11.7.1.11.7.1.21.7.21.8 |
21.7.12 |
virtualenvRoot:PyPI |
before 21.4.3+aikido.1 | 21.4.3+aikido.121.3.2+aikido.120.26.6+aikido.221.4.2+aikido.120.34.0+aikido.420.35.4+aikido.420.34.0+aikido.520.36.1+aikido.420.36.1+aikido.521.7.4+aikido.121.6.1+aikido.121.6.1+aikido.221.5.1+aikido.221.7.8+aikido.120.26.6+aikido.321.7.8+aikido.221.7.1+aikido.221.7.9+aikido.121.7.9+aikido.221.2.4+aikido.221.7.5+aikido.221.7.5+aikido.321.7.7+aikido.121.7.7+aikido.221.7.10+aikido.221.7.10+aikido.321.7.4+aikido.221.7.4+aikido.321.7.4+aikido.420.26.6+aikido.420.26.6+aikido.521.3.2+aikido.221.3.2+aikido.321.7.1+aikido.321.4.3+aikido.221.7.5+aikido.421.2.4+aikido.321.7.9+aikido.321.7.4+aikido.521.7.10+aikido.421.7.8+aikido.321.7.10+aikido.521.7.4+aikido.621.6.1+aikido.321.4.2+aikido.221.7.5+aikido.521.7.1+aikido.421.7.9+aikido.421.4.3+aikido.321.2.4+aikido.421.3.2+aikido.420.39.1+aikido.320.31.2+aikido.3 |
Show 8 moreShow less
| Package | Affected | Fixed |
|---|---|---|
python-virtualenvUbuntu:14.04:LTS |
All versions, plus listed versions 1.10.1-11.11-11.11-21.11.4-11.11.4-1ubuntu1 |
None known |
python-virtualenvUbuntu:16.04:LTS |
All versions, plus listed versions 1.11.6+ds-114.0.5+ds-114.0.5+ds-214.0.5+ds-415.0.0+ds-1 Show 6 moreShow less15.0.0+ds-215.0.1+ds-115.0.1+ds-215.0.1+ds-315.0.1+ds-3ubuntu115.0.1+ds-3ubuntu1.1 |
None known |
python-virtualenvUbuntu:18.04:LTS |
All versions, plus listed versions 15.1.0+ds-115.1.0+ds-1.1 |
None known |
python-virtualenvUbuntu:Pro:20.04:LTS |
All versions, plus listed versions 15.1.0+ds-215.1.0+ds-2build115.1.0+ds-2ubuntu120.0.13-120.0.17-120.0.17-1ubuntu0.320.0.17-1ubuntu0.420.0.17-1ubuntu0.4+esm1 |
None known |
python-virtualenvUbuntu:Pro:22.04:LTS |
All versions, plus listed versions 20.4.6+ds-220.10.0+ds-120.12.1+ds-120.13.0+ds-120.13.0+ds-220.13.0+ds-2ubuntu0.1~esm1 |
None known |
python-virtualenvUbuntu:Pro:24.04:LTS |
All versions, plus listed versions 20.24.1+ds-120.24.6+ds-120.24.6+ds-220.25.0+ds-120.25.0+ds-220.25.0+ds-2ubuntu0.1~esm1 |
None known |
python-virtualenvUbuntu:26.10 |
All versions, plus listed versions 20.36.1+ds-121.4.1+ds-121.5.1+ds-1 |
None known |
python-virtualenvUbuntu:26.04:LTS |
All versions, plus listed versions 20.31.2+ds-120.35.3+ds-120.35.4+ds-120.36.1+ds-1 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-102937 is a high vulnerability (CVSS 7.3) in Pypa Virtualenv, published September 18, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.21%, the 10th percentile. Fixed in virtualenv 21.7.12.
References
github.com/pypa/virtualenv/security/advisories/GHSA-x78j-v8h9-3j2q
nvd.nist.gov/vuln/detail/CVE-2026-102937
Show 7 moreShow less
Left out here: 231 versions. The JSON record has them.