CVE-2026-115557 Distrust compromised intermediate certificates in ssl module
Critical 9.4
Published
Updated
Check this codebase for CVE-2026-115557 and fix it if it is affected.
What it is: CVE-2026-115557 is a critical vulnerability in CPython, published on 24 Oct 2026.
Exploitation: There is no known exploitation of CVE-2026-115557 in the wild and no public exploit code.
Affected product: CPython. No package-level version data is available, so check the vendor advisory linked from the reference page.
Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.
Reference: https://insights.sbomify.com/CVE-2026-115557/ (Markdown: https://insights.sbomify.com/CVE-2026-115557/index.md)
- Exploited in the wild
- Not known
- Fix
- Available
What is CVE-2026-115557?
CVE-2026-115557 is a critical vulnerability in CPython, published on 24 Oct 2026.
Official description
Python has added a denylist for known compromised certificates to the "ssl" module to ensure user safety even without certificate revocation configured. Known compromised certificates will automatically be rejected regardless of the SSLContext policy configuration.
Weakness: CWE-299
Which versions are affected by CVE-2026-115557?
How do I fix CVE-2026-115557?
Upgrade to a fixed version.
Is CVE-2026-115557 being exploited?
There is no known exploitation of CVE-2026-115557 in the wild and no public exploit code.
Sources
Also known as ALPINE-CVE-2026-115557, AZL-111098, AZL-111101, BELL-CVE-2026-115557, DEBIAN-CVE-2026-115557, ECHO-b4e8-96ac-3414 and 3 more.