CVE
Red Hat local denial of service in the sssd PAM responder
- Exploited
- No known exploitation
- Fix
- See vendor advisory
- Who is exposed
- Not reported
- Last modified
- Whether it needs action now or is a reference record, by fixed rules, with why. Last checked is when cve.now last re-read it.What do these mean? →
- Reference
- Last checked
- FIRST's estimate of the chance attackers exploit it in the next 30 days, updated daily.What do these mean? →
- 0.14% · 3rd percentile
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 21/100 · provisional
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: no
- Technical impact: partial
Summary
A flaw in the sssd package used on Red Hat Enterprise Linux and Red Hat OpenShift Container Platform lets a local attacker with low-privilege access crash the PAM responder by sending a crafted authentication request with a non-string OAuth2 code value. This causes a NULL pointer dereference, which disrupts SSSD-backed logins, and the bug only affects builds with the JSON PAM extension enabled.
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
Read the original description
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.
cve.now Index
- Exploitation0/40No signal
- Exposure?/25Unknown. No advisory context yet
- Reach10/20Shipped in major Linux distributions
- Severity5.5/10CVSS 5.5
- No patch5/5No fixed version listed; see vendor advisory
What would change the score
- Would score about 76 if added to CISA KEV
- Would score about 71 if CISA's SSVC rates exploitation active
- Would score about 43 if advisories confirm default setups are exposed
Check your systems with an agent
Paste this into a coding or ops agent. It checks your systems read-only and reports a table per asset.
Check whether my systems are affected by CVE-2026-127100 (Sssd: sssd: local denial of service through unchecked oauth2 json code type in pam responder), using the cve.now data below.
Rules: work read-only. Do not run exploit code, proof-of-concept scripts or scanners that send attack payloads, and do not change any configuration, package, image or deployment. Report findings only.
What cve.now has for CVE-2026-127100 (entry last updated 2026-11-13):
Affected:
- Red Hat Red Hat Enterprise Linux 10: version range not reported
- Red Hat Red Hat Enterprise Linux 6: version range not reported
- Red Hat Red Hat Enterprise Linux 7: version range not reported
- Red Hat Red Hat Enterprise Linux 8: version range not reported
- Red Hat Red Hat Enterprise Linux 9: version range not reported
- Red Hat Red Hat OpenShift Container Platform 4: version range not reported
- Red Hat Red Hat OpenShift Container Platform 4: version range not reported
- Red Hat Red Hat OpenShift Container Platform 5: version range not reported
Fixed versions: none listed yet.
Setup: unknown whether the bug needs a non-default feature or setting. Check the advisory.
CISA KEV: CVE-2026-127100 is not listed as of cve.now's last read.
This KEV status is for CVE-2026-127100 only. If you also check another CVE, look up its own KEV status; never assume it from this one.
How to check:
- Installed software: check what is actually running, not what a repo declares. Read the version from each host, container image and Kubernetes node (the binary's version output, the OS package database, image layers), and check whether the conditions above hold there. Distribution packages may carry a backported fix under an older version number; confirm against the distribution's own advisory.
Verify against the linked advisories before concluding, and cite the date you read each one:
- https://bugzilla.redhat.com/show_bug.cgi?id=2572591
- https://access.redhat.com/security/cve/CVE-2026-127100
Do not conclude an asset is unaffected unless you checked it and the evidence covers both its version and the conditions above. If you could not check something, mark it unknown and say what is missing.
Report a table with one row per asset and these columns: Asset | Version or build | Status (affected, fixed, not applicable, unknown) | Compensating controls | Exposure (internet-facing, internal, none) | Evidence | Next action.
Entry: https://cve.now/CVE-2026-127100
For follow-up questions, use the cve.now MCP server at https://mcp.cve.now/mcp (no authentication), for example execute with name cve.get and arguments {"id": "CVE-2026-127100"}.Timeline
- CVE published
- First seen by cve.now1 day
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: partial
- Record last updated
Affected versions
- sssd
Version range not reported
- sssd
Version range not reported
- sssd
Version range not reported
- sssd
Version range not reported
- sssd
Version range not reported
- openshift/ose-rhel-coreos-8
Version range not reported
- openshift/ose-rhel-coreos-9
Version range not reported
- openshift/ose-rhel-coreos-9
Version range not reported
Evidence 4
CVE record · 2
Establishes: The identifier and description.
- Record
- Record
Write-ups · 1
Establishes: Technical detail and context.
- Report
Other links · 1
- Link
Corrections
None so far.
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