chain.c in back-ldap in OpenLDAP 2.4.x before 2.4.24, when a master-slave configuration with a chain overlay and ppolicy_forward_updates (aka authentication-failure forwarding) is used, allows remote authenticated users to bypass external-program authentication by sending an invalid password to a slave server.
CVE-2011-1024
This CVE was only ever scored under CVSS v2.0. NVD CVSS v2.0 base 4.6 — v2 rates that MEDIUM (v2 bands: LOW 0.0–3.9 / MEDIUM 4.0–6.9 / HIGH 7.0–10.0; v2 has no CRITICAL band). Vector AV:N/AC:H/Au:S/C:P/I:P/A:P. CVSS v2 is an older, coarser metric than v3.1/v4.0 (no Scope, no User Interaction, no Attack Requirements), so it is not directly comparable to a v3 or v4 score. NVD has never re-scored this record under v3. EPSS predicts 3.0% exploitation probability in the next 30 days, which is reflected in EG Risk but does not lift the v2 base. Confidence: LOW.
- Lower severity and no public exploit yet
A fix is available — apply it.
- CVSS v2.0 (legacy)
- 4.6MEDIUMNVD never assigned a CVSS v3 rating to this CVE
- EG Score
- 4.6(low)
- EG Risk
- 26(Track)EG Risk 26/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity46% × 45%Exploitation3% × 40%Automatability30% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 3%
- EPSS %ILE
- 84%
- KEV
- Not listed
Published
March 20, 2011
Last Modified
April 29, 2026
References (42)
- secalert@redhathttp://kb.juniper.net/InfoCenter/index?page=content&id=JSA10705
- secalert@redhathttp://kb.juniper.net/InfoCenter/index?page=content&id=JSA10735
- secalert@redhathttp://openwall.com/lists/oss-security/2011/02/24/12
- secalert@redhathttp://openwall.com/lists/oss-security/2011/02/25/13
- secalert@redhathttp://secunia.com/advisories/43331
- secalert@redhathttp://secunia.com/advisories/43708
- secalert@redhathttp://secunia.com/advisories/43718
- secalert@redhathttp://security.gentoo.org/glsa/glsa-201406-36.xml
- secalert@redhathttp://securitytracker.com/id?1025188
- secalert@redhathttp://www.mandriva.com/security/advisories?name=MDVSA-2011:055
- secalert@redhathttp://www.mandriva.com/security/advisories?name=MDVSA-2011:056
- secalert@redhathttp://www.openldap.org/devel/cvsweb.cgi/servers/slapd/back-ldap/chain.c.diff?r1=1.76&r2=1.77&hideattic=1&sortbydate=0
- secalert@redhathttp://www.openldap.org/its/index.cgi/Software%20Bugs?id=6607
- secalert@redhathttp://www.openldap.org/lists/openldap-announce/201102/msg00000.html
- secalert@redhathttp://www.openldap.org/lists/openldap-technical/201004/msg00247.html
Patch Availability(3)
| Vendor / Ecosystem | Fixed in / Patch | Released | Source |
|---|---|---|---|
| ubuntu | slapd (2.4.23-0ubuntu3.5) @ maverick | 2026-05-29 | ubuntu |
| redhat | openldap-0:2.4.19-15.el6_0.2 | 2011-03-10 | redhat |
| redhat | openldap-0:2.3.43-12.el5_6.7 | 2011-03-10 | redhat |
Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.
Affected Packages
(4 across 4 ecosystems)
Debian:11(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| openldap | — | 2.4.25-1 | — |
Debian:12(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| openldap | — | 2.4.25-1 | — |
Debian:13(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| openldap | — | 2.4.25-1 | — |
Debian:14(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| openldap | — | 2.4.25-1 | — |
All Vendor Advisories
(3)
Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.
Data Freshness Timeline
(refreshed 2× in last 7d / 12× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
Showing the most recent 100 of 122 total refreshes for this CVE.
- 2026-08-25 13:43 UTCEPSS rescore
- 2026-08-24 14:02 UTCOSV refresh
- 2026-08-19 16:58 UTCEPSS rescore
- 2026-08-18 13:42 UTCEPSS rescore
- 2026-08-15 01:25 UTCEPSS rescore
- 2026-08-08 16:31 UTCEPSS rescore
- 2026-08-08 08:56 UTCOSV refresh
- 2026-08-06 13:41 UTCEPSS rescore
- 2026-08-05 19:12 UTCEPSS rescore
- 2026-08-04 15:04 UTCEPSS rescore
- 2026-08-01 04:10 UTCEPSS rescore
- 2026-07-30 01:26 UTCEPSS rescore
- 2026-07-26 13:42 UTCEG score recompute▲ 4.60
- 2026-07-23 14:14 UTCEPSS rescore
- 2026-07-23 02:10 UTCOSV refresh
- 2026-07-23 01:04 UTCEG score recompute
- 2026-07-23 00:40 UTCEG score recompute
- 2026-07-23 00:08 UTCEG score recompute
- 2026-07-22 21:47 UTCEG score recompute
- 2026-07-22 14:03 UTCEPSS rescore
- 2026-07-21 15:21 UTCEPSS rescore
- 2026-07-20 17:03 UTCEPSS rescore
- 2026-07-20 17:03 UTCEPSS rescore
- 2026-07-19 02:25 UTCEPSS rescore
- 2026-07-19 02:25 UTCEPSS rescore
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- 2026-07-18 10:00 UTCEPSS rescore
- 2026-07-16 16:58 UTCEPSS rescore
- 2026-07-15 16:54 UTCEPSS rescore
- 2026-07-15 16:54 UTCEPSS rescore
- 2026-07-15 01:55 UTCEPSS rescore
- 2026-07-13 22:25 UTCEPSS rescore
- 2026-07-11 08:22 UTCEPSS rescore
- 2026-07-11 08:22 UTCEPSS rescore
- 2026-07-08 15:10 UTCEPSS rescore
- 2026-07-08 15:10 UTCEPSS rescore
- 2026-07-06 16:23 UTCEPSS rescore
- 2026-07-06 02:19 UTCEPSS rescore
- 2026-07-06 02:19 UTCEPSS rescore
- 2026-07-05 20:59 UTCOSV refresh
- 2026-07-05 02:26 UTCEPSS rescore
- 2026-07-04 06:27 UTCEPSS rescore
- 2026-07-02 14:01 UTCEPSS rescore
- 2026-07-01 15:02 UTCEPSS rescore
- 2026-07-01 15:02 UTCEPSS rescore
- 2026-06-30 23:19 UTCEPSS rescore
- 2026-06-30 23:19 UTCEPSS rescore
- 2026-06-29 14:02 UTCEPSS rescore
- 2026-06-28 04:53 UTCEPSS rescore
- 2026-06-28 04:52 UTCEPSS rescore
- 2026-06-27 03:05 UTCEPSS rescore
- 2026-06-27 03:05 UTCEPSS rescore
- 2026-06-25 13:46 UTCEPSS rescore
- 2026-06-24 14:02 UTCEPSS rescore
- 2026-06-24 14:02 UTCEPSS rescore
- 2026-06-22 14:22 UTCEPSS rescore
- 2026-06-22 14:22 UTCEPSS rescore
- 2026-06-21 01:56 UTCEPSS rescore
- 2026-06-21 01:56 UTCEPSS rescore
- 2026-06-19 19:22 UTCEPSS rescore
- 2026-06-19 19:22 UTCEPSS rescore
- 2026-06-18 17:49 UTCEPSS rescore
- 2026-06-18 17:49 UTCEPSS rescore
- 2026-06-17 17:49 UTCEPSS rescore
- 2026-06-17 17:49 UTCEPSS rescore
- 2026-06-17 17:49 UTCEPSS rescore
- 2026-06-17 08:13 UTCOSV refresh
- 2026-06-16 17:49 UTCEPSS rescore
- 2026-06-15 17:44 UTCEPSS rescore
- 2026-06-14 23:14 UTCEPSS rescore
- 2026-06-14 23:14 UTCEPSS rescore
- 2026-06-13 22:57 UTCEPSS rescore
- 2026-06-13 22:57 UTCEPSS rescore
- 2026-06-12 23:08 UTCEPSS rescore
- 2026-06-11 13:56 UTCEPSS rescore
- 2026-06-10 22:14 UTCEPSS rescore
- 2026-06-10 13:17 UTCEPSS rescore
- 2026-06-08 14:14 UTCEPSS rescore
- 2026-06-08 14:14 UTCEPSS rescore
- 2026-06-07 15:22 UTCEPSS rescore
- 2026-06-07 15:22 UTCEPSS rescore
- 2026-06-06 13:45 UTCEPSS rescore
- 2026-06-06 13:44 UTCEPSS rescore
- 2026-06-05 22:44 UTCEPSS rescore
- 2026-06-05 06:08 UTCEPSS rescore
- 2026-06-05 06:07 UTCEPSS rescore
- 2026-06-04 13:09 UTCEPSS rescore
- 2026-06-04 13:09 UTCEPSS rescore
- 2026-06-02 20:10 UTCEPSS rescore
- 2026-06-02 20:10 UTCEPSS rescore
- 2026-06-01 13:49 UTCEPSS rescore
- 2026-06-01 13:49 UTCEPSS rescore
- 2026-05-31 22:28 UTCEPSS rescore
- 2026-05-31 22:28 UTCEPSS rescore
- 2026-05-31 00:14 UTCEPSS rescore
- 2026-05-31 00:14 UTCEPSS rescore
- 2026-05-29 13:41 UTCEPSS rescore
- 2026-05-29 13:40 UTCEPSS rescore
- 2026-05-29 08:28 UTCEG score recompute
- 2026-05-29 08:28 UTCVendor advisory
- 2026-05-29 08:28 UTCGHSA enrichment
Frequently asked(4)
What is CVE-2011-1024?
When was CVE-2011-1024 disclosed?
Is CVE-2011-1024 actively exploited?
How do I remediate CVE-2011-1024?
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2011-1024
Is Your Infrastructure Affected by CVE-2011-1024?
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