GHSA-q623-f4j4-p4xj: keystone (CVE-2026-43000)

Package	Ecosystem	Affected	Fixed in
keystone	PyPI	>=14.0.0, <27.0.2 \|\| >=28.0.0, <28.0.2 \|\| >=29.0.0, <29.0.2	27.0.2, 28.0.2, 29.0.2

Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

Keystone (the PyPI package keystone) versions 14.0.0 up to 27.0.2, 28.0.0 up to 28.0.2, and 29.0.0 up to 29.0.2 are affected. An attacker holding the member role on a project, and able to combine an application credential impersonation weakness with trust creation, can create a trust that delegates the victim's admin role to themselves and so escalate to admin. Upgrade to 27.0.2, 28.0.2, or 29.0.2, depending on the release line in use.

Written 1 Nov 2026.

Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

Severity and exploitation

Score	Rating	CVSS	Vector	Source
6.0	Medium	3.1	CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:L	CNA (mitre)

CISA KEV Not listed.
EPSS 0.0033, the 26th percentile, on 15 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

31 Oct 2026, 14:11 UTC First seen by agentprime
31 Oct 2026, 14:11 UTC Confirmed by OSV

Sources

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.