CVE-2026-15722
A stack buffer overflow flaw was found in 389 Directory Server (389-ds-base). The get_ruvelement_from_berval() function in repl5_ruv.c copies digit characters from a network-supplied RUV berval into a fixed 16-byte stack buffer without bounds checking. A remote unauthenticated attacker can crash the LDAP server by sending a crafted StartNSDS50ReplicationRequest extended operation containing a replica ID field with more than 16 digit characters. The overflow occurs during payload decoding, before any authorization check. Stack protectors limit impact to denial of service.
Executive briefing
The source record describes: A stack buffer overflow flaw was found in 389 Directory Server (389-ds-base). The get_ruvelement_from_berval() function in repl5_ruv.c copies digit characters from a network-supplied RUV berval into a fixed 16-byte stack buffer without bounds checking. A remote unauthenticated attacker can crash the LDAP server by sending a crafted StartNSDS50ReplicationRequest extended operation containing a replica ID field with more than 16 digit characters. The overflow occurs during payload decoding, before any authorization check. Stack protectors limit impact to denial of service. The practical risk depends on whether an affected product/version is present, reachable and configured in an exploitable way. Review the affected-product evidence and linked vendor advisories before assigning exposure status.
Evidence confidence: Moderate Evidence-derived, not an exploitability verdict
Severity & attack characteristics
CVSS vector:CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Technical explanation & impact
The technical mechanism is not expanded beyond the source description unless a referenced advisory supplies additional evidence. Read the linked vendor/CERT advisories for root-cause detail.
Potential impact must be interpreted from the published CVSS impact metrics and the affected component. A CVSS impact score is not proof that a particular asset is exploitable.
Weakness classification
CWE-121Affected products and versions
Products below are parsed from NVD vulnerable CPE configuration entries. Version boundaries are shown as published; verify applicability with the vendor.
| Vendor | Product | Version evidence |
|---|---|---|
| redhat | directory_server | CPE version 11.0 · CPE version 12.0 |
| redhat | 389_directory_server | Version not specified in CPE |
| redhat | enterprise_linux | CPE version 7.0 · CPE version 8.0 · CPE version 9.0 · CPE version 10.0 |
Remediation & validation
- Identify exposure by comparing the affected product and version ranges with your asset inventory, SBOM and externally exposed services.
- Review the linked vendor security advisory or patch notes. Upgrade to a vendor-confirmed fixed release; do not infer a fixed version from the CVE description.
- Until patched, consider restricting network access or disabling the affected feature where operationally safe. These are temporary controls, not a substitute for a vendor fix.
- Validate the remediation with a version check and vulnerability rescan, then retain change evidence.
No fixed version is displayed unless it is explicitly established by a vendor advisory. Follow the vendor's release notes for exact product and branch applicability.
Vendor advisories, patches & exploit references
- https://access.redhat.com/errata/RHSA-2026:55421 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:55422 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:55423 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:55424 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:55425 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:55426 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:55530 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:55532 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:55756 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:55757 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:55758 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:55794 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:56047 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:56048 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:56050 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:79217 VENDOR secalert@redhat.com
- https://access.redhat.com/security/cve/CVE-2026-15722 ADVISORY secalert@redhat.com
- https://bugzilla.redhat.com/show_bug.cgi?id=2499961 ADVISORY secalert@redhat.com