python-utcp: Cleartext Storage of Sensitive Information in an Environment Variable
CVE-2026-45370 is a high-severity cleartext storage of sensitive information in an environment variable vulnerability in python-utcp from Universal-tool-calling-protocol, with a CVSS 3.1 base score of 7.7 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected python-utcp versions: < 1.1.2. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.22% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of python-utcp you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Universal-tool-calling-protocol | python-utcp | < 1.1.2 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- NoneNothing can be modified.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N. Scored by CNA (github.com).
Official description
python-utcp is the python implementation of UTCP. Prior to 1.1.3, _prepare_environment() in cli_communication_protocol.py passes a full copy of os.environ to every CLI subprocess. When combined with CVE-2026-45369, an attacker can exfiltrate all process-level secrets in a single tool call. This vulnerability is fixed in 1.1.3.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Cleartext Storage of Sensitive Information in an Environment Variable
The product uses an environment variable to store unencrypted sensitive information.
How developers prevent this class of flaw
- If the environment variable is not necessary for the desired behavior, then remove it entirely, or clear it to an empty value.
More Cleartext Storage of Sensitive Information in an Environment Variable vulnerabilities (CWE-526)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Other vulnerabilities in python-utcp
- 8.2 High severity
- 7.1 High severity
- 8.3 High severity
Recent Cleartext Storage of Sensitive Information in an Environment Variable vulnerabilities
- 7.0 High severity
- 7.5 High severity
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