---
id: "CVE-2026-127100"
page: "https://infrastack.ai/live/CVE-2026-127100"
kind: "vulnerability"
aliases: ["CVE-2026-127100"]
title: "SSSD: crafted PAM request crashes authentication responder on JSON builds"
severity: "medium"
cvss: 5.5
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: [{"name": "sssd", "fixed": [], "affected": "", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["infrastructure", "linux", "pam", "self-hosted", "sssd"]
not_affected_if: ["default-build", "no-local-access"]
published_at: "2026-11-12T18:17:40+00:00"
first_seen_at: "2026-11-12T18:40:39+00:00"
updated_at: "2026-11-12T18:43:01+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-127100", "first_seen_at": "2026-11-12T18:40:39+00:00"}]
exploit_sources: []
---

# SSSD: crafted PAM request crashes authentication responder on JSON builds

Link for people: https://infrastack.ai/live/CVE-2026-127100 (this .md is for agents)

SSSD's PAM responder, when built with the JSON PAM extension, dereferences a NULL pointer if an authentication request carries a non-string OAuth2 code value. A local attacker can crash the responder and disrupt SSSD-backed logins.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:sssd affected range not listed fixed no fixed version listed

## Timeline

- 2026-11-12T18:40:39+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-127100

## From the sources

A flaw was found in SSSD's PAM responder on builds with the JSON PAM extension enabled. A local attacker can submit a crafted authentication request containing a non-string OAuth2 code value. Missing JSON type validation leads to a NULL pointer dereference, terminating the PAM responder and disrupting SSSD-backed authentication.

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