AnyIO run_process/open_process ignores extra_groups and can retain parent supplementary groups (agronholm anyio)

CVE-2026-63349
HIGH 7.0

At a glance

Source
NVD
EPSS
EPSS 0.11 % · percentile 1 ()
State
PUBLISHED
Published
Updated
Assigner
GitHub_M
NVD status
Awaiting Analysis

Description

AnyIO is a high level asynchronous concurrency and networking framework that works on top of either Trio or asyncio. In 4.14.0, AnyIO accepts the POSIX extra_groups argument in anyio.run_process() and anyio.open_process(), but open_process() forwards the group argument to the backend instead of extra_groups. A caller that supplies extra_groups=[] to clear inherited supplementary groups can therefore launch a child that retains the parent process groups, undermining a privilege-dropping boundary. If group is also supplied, the integer group value is passed where an iterable of supplementary groups is expected and the launch can fail with TypeError. This issue affects POSIX applications that rely on AnyIO subprocess helpers to launch less-privileged child processes. This issue is fixed in version 4.14.2.

Weaknesses (CWE)

  • CWE-266 — Incorrect Privilege Assignment
  • CWE-269 — Improper Privilege Management

References

Scores

VersionScoreVectorScored by
CVSS 4.0HIGH 7.0CVSS:4.0/AV:L/AC:H/AT:P/PR:H/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:NGitHub_M
CVSS 4.0HIGH 7.0CVSS:4.0/AV:L/AC:H/AT:P/PR:H/UI:N/VC:H/VI:H/VA:N/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:XNVD · security-advisories@github.com (Secondary)

Advisories

European references

CERT-FR advisories

Affected products

ProductVersions
agronholm · anyioaffected >= 4.14.0, < 4.14.2

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD