The deref_parseCtrl function in servers/slapd/overlays/deref.c in OpenLDAP 2.4.13 through 2.4.40 allows remote attackers to cause a denial of service (NULL pointer dereference and crash) via an empty attribute list in a deref control in a search request.
Conclusion & alert: CVE-2015-1545 is rated High Exploit Risk (64.4/100): CVSS Medium severity, with high exploitation likelihood (EPSS 64.84%, 98th percentile). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
| EDB-ID | Source | Kind | Published | Link |
|---|---|---|---|---|
| — | nvd_ref | exploit_tag | Exploit-DB ↗ |
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2025-10-07 | 72.59% | 64.84% | -7.75% |
| 2 | 2025-05-04 | 64.84% | 72.59% | +7.75% |
| 3 | 2025-03-30 | — | 64.84% | — |
Full EPSS history (9 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 5.0 | 2.0 | MEDIUM |
|
10.0 | 2.9 | [email protected] |
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
not yet assigned | CVE-2015-1545 not yet assigned priority: Debian including 1 source packages (openldap), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. | https://security-tracker.debian.org/tracker/CVE-2015-1545 |
redhat
|
medium | — | https://access.redhat.com/security/cve/CVE-2015-1545 |
ubuntu
|
low | CVE-2015-1545 low priority: Ubuntu including 1 source packages (openldap), 6 status rows across 6 suites (lucid, precise, trusty, upstream, utopic, vivid): released 5, ignored 1. | https://ubuntu.com/security/CVE-2015-1545 |
: <a href="http://cwe.mitre.org/data/definitions/476.html">CWE-476: NULL Pointer Dereference</a>
Note that the deref overlay is not enabled by default, so this vulnerability only affects sites that have explicitly configured their servers to load and enable the overlay. Since this overlay has never been documented, there are no sites outside of the OpenLDAP developer community with a legitimate reason to enable this module.
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| openldap | openldap | 2.4.13 | cpe:2.3:a:openldap:openldap:2.4.13:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.14 | cpe:2.3:a:openldap:openldap:2.4.14:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.15 | cpe:2.3:a:openldap:openldap:2.4.15:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.16 | cpe:2.3:a:openldap:openldap:2.4.16:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.17 | cpe:2.3:a:openldap:openldap:2.4.17:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.18 | cpe:2.3:a:openldap:openldap:2.4.18:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.19 | cpe:2.3:a:openldap:openldap:2.4.19:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.20 | cpe:2.3:a:openldap:openldap:2.4.20:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.21 | cpe:2.3:a:openldap:openldap:2.4.21:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.22 | cpe:2.3:a:openldap:openldap:2.4.22:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.23 | cpe:2.3:a:openldap:openldap:2.4.23:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.24 | cpe:2.3:a:openldap:openldap:2.4.24:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.25 | cpe:2.3:a:openldap:openldap:2.4.25:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.26 | cpe:2.3:a:openldap:openldap:2.4.26:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.27 | cpe:2.3:a:openldap:openldap:2.4.27:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.28 | cpe:2.3:a:openldap:openldap:2.4.28:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.29 | cpe:2.3:a:openldap:openldap:2.4.29:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.30 | cpe:2.3:a:openldap:openldap:2.4.30:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.31 | cpe:2.3:a:openldap:openldap:2.4.31:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.32 | cpe:2.3:a:openldap:openldap:2.4.32:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.33 | cpe:2.3:a:openldap:openldap:2.4.33:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.34 | cpe:2.3:a:openldap:openldap:2.4.34:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.35 | cpe:2.3:a:openldap:openldap:2.4.35:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.36 | cpe:2.3:a:openldap:openldap:2.4.36:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.37 | cpe:2.3:a:openldap:openldap:2.4.37:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.38 | cpe:2.3:a:openldap:openldap:2.4.38:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.39 | cpe:2.3:a:openldap:openldap:2.4.39:*:*:*:*:*:*:* |
| openldap | openldap | 2.4.40 | cpe:2.3:a:openldap:openldap:2.4.40:*:*:*:*:*:*:* |