Double free in Red Hat Directory Server 11
Priority LOW 27CWE-415Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Deferred Red Hat: fix deferred
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-415 and the CVSS impact.
Summary
A flaw was found in 389-ds-base. The get_ldapmessage_controls_ext() function frees the parsed controls array on the Session Tracking critical-control rejection path without clearing the SLAPI_REQCONTROLS pblock slot. Operation teardown then frees the same pointer again, causing a double-free. An unauthenticated remote attacker can trigger this with a single BIND request carrying a critical Session Tracking control, resulting in heap corruption and potential denial of service.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00511 43rd percentileScored 2026-11-07
Fix Deferred Red Hat: fix deferred
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Red Hat | Red Hat Directory Server 11 | — | — | Not affected | CNA |
| Red Hat | Red Hat Directory Server 12 | — | — | Not affected | CNA |
| Red Hat | Red Hat Directory Server 13 | — | — | No fix listed | CNA |
| Red Hat | Red Hat Enterprise Linux 10 | — | — | No fix listed | CNA |
| Red Hat | Red Hat Enterprise Linux 6 | — | — | Not affected | CNA |
| Red Hat | Red Hat Enterprise Linux 7 | — | — | Not affected | CNA |
| Red Hat | Red Hat Enterprise Linux 8 | — | — | Not affected | CNA |
| Red Hat | Red Hat Enterprise Linux 9 | — | — | Not affected | CNA |
- Red Hat Directory Server 11 VendorRed Hat Affected — Fixed in — Not affected CNA
- Red Hat Directory Server 12 VendorRed Hat Affected — Fixed in — Not affected CNA
- Red Hat Directory Server 13 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat Enterprise Linux 10 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat Enterprise Linux 6 VendorRed Hat Affected — Fixed in — Not affected CNA
- Red Hat Enterprise Linux 7 VendorRed Hat Affected — Fixed in — Not affected CNA
- Red Hat Enterprise Linux 8 VendorRed Hat Affected — Fixed in — Not affected CNA
- Red Hat Enterprise Linux 9 VendorRed Hat Affected — Fixed in — Not affected CNA
CPE names CNA · 8
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:/a:redhat:directory_server:11 | 11 | — | Red Hat |
| cpe:/a:redhat:directory_server:12 | 12 | — | Red Hat |
| cpe:/a:redhat:directory_server:13 | 13 | — | Red Hat |
| cpe:/a:redhat:enterprise_linux:10 | 10 | — | Red Hat |
| cpe:/o:redhat:rhel_els:6 | 6 | — | Red Hat |
| cpe:/o:redhat:rhel_els:7 | 7 | — | Red Hat |
| cpe:/a:redhat:enterprise_linux:8 | 8 | — | Red Hat |
| cpe:/a:redhat:enterprise_linux:9 | 9 | — | Red Hat |
- cpe:/a:redhat:directory_server:11 Versions 11 — ·Red Hat
- cpe:/a:redhat:directory_server:12 Versions 12 — ·Red Hat
- cpe:/a:redhat:directory_server:13 Versions 13 — ·Red Hat
- cpe:/a:redhat:enterprise_linux:10 Versions 10 — ·Red Hat
- cpe:/o:redhat:rhel_els:6 Versions 6 — ·Red Hat
- cpe:/o:redhat:rhel_els:7 Versions 7 — ·Red Hat
- cpe:/a:redhat:enterprise_linux:8 Versions 8 — ·Red Hat
- cpe:/a:redhat:enterprise_linux:9 Versions 9 — ·Red Hat
Remediation
No fixed version listed by the sources yet.
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Directory Server 13 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 10 | Affected | No fix yet: Fix deferred |
Not affected: 6 products
- Red Hat Directory Server 11
- Red Hat Directory Server 12
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
Timeline
- 2026-10-02 Threatist record created from CVE-2026-18663
- 2026-10-03 Alias added: GHSA-m545-9vp4-qjrp
References
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Sources
- CVE-2026-18663 · CVE Program
- CVE-2026-18663 · NVD
- FIRST EPSS
- GHSA-m545-9vp4-qjrp · GitHub Advisory Database · CC BY 4.0
- CVE-2026-18663 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences