Red Hat RRDtool Updates Fix RHEL 9 Memory-Safety Flaw
Tech GuruQuick Answer
RRDtool's cache daemon can overflow a stack buffer while processing an oversized CREATE request. Red Hat describes a local attacker with access to the rrdcached socket. RHEL 9.2 and 9.4 E4S have different fixed builds; use the package for your entitled stream.
Confirm Scope And Apply The Supported Fix
Next step: Check where rrdcached runs and who can access its socket. Update from the matching RHEL 9.2 or 9.4 Update Services for SAP Solutions repository, then restart the affected daemon and check its clients.
Last verified: 2026-09-28 UTC. Recheck the authoritative advisory and supported distribution channel before changing production.
Scope And Authority
| Product scope | RHEL 9.2 and 9.4 E4S rrdtool packages before the branch-specific fixed builds |
|---|---|
| Advisory | RHSA-2026:72277 / RHSA-2026:72278 |
| CVE | CVE-2026-43958 |
| Authoritative release date | RHSA-2026:72277: 2026-09-28 03:08:13 UTC; RHSA-2026:72278: 2026-09-28 03:08:33 UTC |
| Authority revision date | RHSA-2026:72277: 2026-09-28 03:30:36 UTC; RHSA-2026:72278: 2026-09-28 03:30:15 UTC |
| Affected versions | Entitled RHEL 9.2 and RHEL 9.4 Update Services for SAP Solutions systems with advisory-listed rrdtool packages before the fixed branch build. |
| Fixed version | rrdtool 1.7.2-21.el9_2.1 / 1.7.2-21.el9_4.1 |
| CVSS base score | 7.8 (CVSS v3.1) |
| CVSS severity | High |
| Exploitation status | Not stated by the authority; no exploitation claim is inferred. |
What Changed
CVE-2026-43958 can cause a crash or code execution in the daemon's context. Socket access is part of the stated attack path; the notice does not establish anonymous Internet access on every installation. Red Hat's Moderate advisory rating and the CVE's 7.8 High base score are different assessments, not interchangeable labels.
What To Validate Now
- Inventory. Locate RHEL 9.2 and 9.4 E4S rrdtool packages before the branch-specific fixed builds deployments, versions, enabled features, exposure paths, owners, and dependent services.
- Establish applicability. Compare each deployment with the authority's affected-version statement: Entitled RHEL 9.2 and RHEL 9.4 Update Services for SAP Solutions systems with advisory-listed rrdtool packages before the fixed branch build. Do not infer applicability from product family or severity alone.
- Remediate. Apply rrdtool 1.7.2-21.el9_2.1 / 1.7.2-21.el9_4.1 through the supported vendor or project channel, following the current advisory and change-control requirements.
- Validate. Confirm the installed package and running daemon, socket ownership and permissions, graph generation, and representative data updates. Check monitoring gaps and queued writes after restart. Run malformed-request regression tests only in an isolated environment.
- Retain evidence. Preserve asset and owner identifiers, the applicability decision, before-and-after versions, change approval, installation output, validation results, and any exception or rollback record.
Operational Cautions
Use the exact supported release stream and repository. Test dependencies, clusters, integrations, and rollback before broad deployment; a CVSS rating or reachable feature is not evidence of exploitation.
Evidence To Retain
- Exact product, release stream, package or application version, enabled feature, environment, and accountable owner.
- UTC timestamps, authority revision, approved change record, installer or package-manager output, and resulting version.
- Relevant logs and monitoring evidence, test results, exceptions, compensating controls, and rollback decisions.
Related TechGeeks Resources
Authoritative References
Correction policy: If the authority changes affected versions, fixed versions, severity, exploitation information, mitigations, or required action, TechGeeks will update this notice and its verification date.
