Out-of-Bounds Write in SSSD's NFS idmap plugin (CVE-2026-104036)
Summary
Out-of-bounds write in SSSD's NFS idmap plugin (CVE-2026-104036). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
A flaw was found in SSSD's NFS idmap plugin. When retrieving cached user or group names, the plugin detects if an entry exceeds the destination buffer size but fails to abort before copying data. A local attacker can trigger this vulnerability by requesting identity lookups that resolve to oversized cached entries, resulting in an out-of-bounds write. This flaw primarily leads to a Denial of Service (DoS) by crashing the identity mapping service, and may also corrupt adjacent process memory.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-104036 has been found in SSSD's NFS idmap plugin.
Risk of unauthorized operations or information disclosure. CVSS score: 5.8/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "SSSD's NFS idmap plugin CVE-2026-104036" on the vendor's site.
CVE-2026-104036 (SSSD's NFS idmap plugin) — CWE-787 / CVSS v3 5.8
Attack vector: local / no user interaction
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
Out-of-bounds write (CWE-787) exists in SSSD's NFS idmap plugin.
Check the vendor advisory for the affected versions of SSSD's NFS idmap plugin.
Severity: Medium (CVSS 5.8/10). Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで SSSD's NFS idmap plugin を使っているサービスとバージョンを洗い出す。
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2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
References
- web secalert@redhat.com
- web secalert@redhat.com
- web nvd.nist.gov
- web github.com