📖 ~4 min read • Source: SUSE advisory RHSA-2026:1334 (see also SUSE bugzilla)
Related CVEs: CVE-2026-0861 CVE-2025-4802 CVE-2024-33599 CVE-2024-33600 CVE-2024-2961 CVE-2023-6246 CVE-2023-6779 CVE-2023-6780 +12 more
Upstream summary: Passing too large an alignment to the memalign suite of functions (memalign, posix_memalign, aligned_alloc) in the GNU C Library version 2.30 to 2.42 may result in an integer overflow, which could consequently result in a heap corruption. Note that the attacker must have control over both, the size as well as the alignment arguments of the memalign function to be able to exploit this. The size parameter must be close enough to PTRDIFF_MAX so as to overflow size_t along with t
Table of contents
Symptom & Impact
On SLES 15 hosts running nscd, administrators report behaviour consistent with SUSE advisory RHSA-2026:1334: zypper refusing to install or restart affected services, AppArmor profile warnings in journalctl, and — for security-rated advisories — exposure to the vulnerability set above. In production estates the visible impact ranges from a single service restart to wider availability incidents whenever nscd sits on the serving path.
Environment & Reproduction
Reproduction targets SLES 15. Confirm release with cat /etc/os-release and SUSEConnect --status-text, and the currently installed package with rpm -q nscd. Capture system state with supportconfig -R /var/tmp -B nscd if you need to attach evidence to a SUSE support case. Trigger the workflow that exposes nscd — multiple vulnerabilities (20 CVEs) — patch and remediation guide while collecting journalctl -b, zypper history, and rpm -qa output.
Root Cause Analysis
Root cause is documented in SUSE advisory RHSA-2026:1334. Upstream maintainers shipped fixes in the corresponding nscd update for SLES 15; running an outdated build leaves the host exposed to the failure modes described in the advisory. Correlate journalctl --since timestamps with zypper history entries and any AppArmor denials in /var/log/audit/audit.log to isolate the originating change.
Quick Triage
Quick triage: run systemctl status nscd, journalctl -u nscd -n 200, zypper patch-check, zypper lp, firewall-cmd --list-all, and aa-status. If AppArmor is in enforce mode, capture journalctl -k | grep apparmor to surface denials linked to nscd — multiple vulnerabilities (20 CVEs) — patch and remediation guide.
Step-by-Step Diagnosis
1) Confirm symptom with systemctl --failed. 2) Inspect logs: journalctl -xe and journalctl -u nscd. 3) Validate firewall: firewall-cmd --list-all-zones. 4) Check AppArmor: aa-status and journalctl -k | grep apparmor. 5) Verify package integrity: rpm -V nscd and zypper verify. 6) Correlate findings with zypper history, /var/log/zypp/history, and SUSE advisory RHSA-2026:1334 to pin the change that introduced nscd — multiple vulnerabilities (20 CVEs) — patch and remediation guide.
Solution – Primary Fix
Primary fix for nscd — multiple vulnerabilities (20 CVEs) — patch and remediation guide: apply the corrective zypper transaction described in SUSE advisory RHSA-2026:1334, reload the affected systemd unit, and reconcile firewalld and AppArmor state. Typical commands: sudo zypper ref, sudo zypper -n patch or sudo zypper -n update nscd, sudo systemctl daemon-reload, sudo systemctl restart nscd, then rpm -q nscd to validate the new build is installed. For kernel advisories add sudo systemctl reboot or schedule a Live Patch (kgraft/klp) where covered by your SUSE subscription.
Need help rolling this patch across a SUSE fleet? Our IT Solutions & Services team manages SUSE patch windows with zero-downtime change controls. Get in touch for a free consultation.
Solution – Alternative Approaches
Alternatives include rolling back the offending transaction with sudo zypper history --rollback <id> (Btrfs Snapper snapshots make this safe on SLES 15), locking the package via sudo zypper al nscd, switching firewalld backends between nftables and iptables in /etc/firewalld/firewalld.conf, or temporarily disabling the AppArmor profile with sudo aa-disable /etc/apparmor.d/usr.sbin.nscd to confirm policy is the cause before authoring a custom profile. Where Live Patching is licensed, klp patches applies kernel fixes without reboot.
Verification & Acceptance Criteria
Acceptance: rpm -q nscd shows the expected fixed version, systemctl is-active nscd returns active, journalctl -u nscd --since "5 minutes ago" shows no errors, zypper patch-check reports zero open patches for this advisory, firewall-cmd --list-services includes the required services, aa-status reports the intended profile mode, and the original reproduction steps for nscd — multiple vulnerabilities (20 CVEs) — patch and remediation guide no longer trigger the failure across two consecutive runs.
Rollback Plan
Capture state with zypper history list, snapper list, and rpm -qa > /root/rpm-pre.txt before any change. To revert, run sudo snapper undochange <pre>..<post> on Btrfs deployments or sudo zypper install --oldpackage nscd-<old-version> and reload systemctl daemon-reload. Remove custom AppArmor profiles with sudo apparmor_parser -R. Reboot if the kernel or initramfs was changed and re-verify symptoms.
Prevention & Hardening
Prevent recurrence by enabling automatic security patches with zypper-automatic or YaST > Online Update Configuration, subscribing to the SUSE-SU mailing list, mirroring through SUSE Manager / RMT for controlled rollouts, version-locking sensitive packages with zypper al, and monitoring file integrity with aide --check. Apply CIS SLES 15 hardening, enable Snapper rollbacks on Btrfs root, and where supported enable SUSE Live Patching so future advisories like this can be remediated without reboot.
Related Errors & Cross-Refs
Related issues that commonly surface alongside nscd — multiple vulnerabilities (20 CVEs) — patch and remediation guide: zypper transaction lock contention, systemd unit ordering cycles, AppArmor denials in journalctl -k, firewalld zone drift, and kernel taint flags shown by cat /proc/sys/kernel/tainted. See sibling common-problem articles in this SLES 15 series for adjacent failure modes.
View all sles-15 tutorials on the Tutorials Hub →
Browse all common problems & solutions on the Tutorials Hub.
References & Further Reading
Primary reference: SUSE advisory RHSA-2026:1334 (see also SUSE bugzilla). Supporting docs: SUSE Linux Enterprise Server Administration Guide, man zypper, man systemctl, man firewall-cmd, man aa-status, man snapper, man journalctl, the SUSE patch finder at suse.com/patches/, and the SUSE Live Patching documentation. Review /usr/share/doc/packages/nscd/ for component-level notes implicated in nscd — multiple vulnerabilities (20 CVEs) — patch and remediation guide.
