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CVE-2009-3767· NVD / CVE Program· CNA mitre

libraries/libldap/tls_o.c in OpenLDAP 2.2 and 2.4, and possibly other versions, when OpenSSL is used, does not properly handle a '\0' charac

Noroxi assessment

Priority: Monitor (action score 18/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 3.2% (FIRST EPSS); higher than 88.2% of all records.
  • Fixed version: openldap (Debian:12) 2.4.17-2.1; openldap2.3 (Debian:4.0) 2.3.30-5+etch3; openldap (Debian:5.0) 2.4.11-1+lenny1.

Low priority for now. Upgrade to openldap (Debian:12) 2.4.17-2.1; openldap2.3 (Debian:4.0) 2.3.30-5+etch3; openldap (Debian:5.0) 2.4.11-1+lenny1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

libraries/libldap/tls_o.c in OpenLDAP 2.2 and 2.4, and possibly other versions, when OpenSSL is used, does not properly handle a '\0' character in a domain name in the subject's Common Name (CN) field of an X.509 certificate, which allows man-in-the-middle attackers to spoof arbitrary SSL servers via a crafted certificate issued by a legitimate Certification Authority, a related issue to CVE-2009-2408.

MediumCVSS 4.3 · v2.0—No exploit Fix available
Published
Oct 23, 2009
Updated
Jun 16, 2026
EPSS
3.2% · 88th percentile

Report tools

JSON

Action score

18

Monitor

Low priority for now.

CVSS
17 / 40 · 4.3 / 10
CISA KEV
0 / 30 · Not listed
EPSS
1 / 30 · 3.2%

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

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When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
openldapopenldap
opensslopenssl
applemac os x
fedoraprojectfedora

Check your site's encryption

This vulnerability is about certificate validation or weak cryptography. The free SSL checker tests your certificate, enabled TLS versions and weak ciphers.

Run the SSL check

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • apple mac os xbefore 10.6.2
  • fedoraproject fedora11
  • openldap openldapbefore 2.4.18

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:12openldapbefore 2.4.17-2.12.4.17-2.1
Debian:4.0openldap2.3before 2.3.30-5+etch32.3.30-5+etch3
Debian:5.0openldapbefore 2.4.11-1+lenny12.4.11-1+lenny1
Red Hat:enterprise_linux:4::ascompat-openldapbefore 0:2.1.30-12.el4_8.30:2.1.30-12.el4_8.3
Red Hat:enterprise_linux:4::asopenldapbefore 0:2.2.13-12.el4_8.30:2.2.13-12.el4_8.3
Red Hat:enterprise_linux:4::asopenldap-clientsbefore 0:2.2.13-12.el4_8.30:2.2.13-12.el4_8.3
Red Hat:enterprise_linux:4::asopenldap-debuginfobefore 0:2.2.13-12.el4_8.30:2.2.13-12.el4_8.3
Red Hat:enterprise_linux:4::asopenldap-develbefore 0:2.2.13-12.el4_8.30:2.2.13-12.el4_8.3
Red Hat:enterprise_linux:4::asopenldap-serversbefore 0:2.2.13-12.el4_8.30:2.2.13-12.el4_8.3
Red Hat:enterprise_linux:4::asopenldap-servers-sqlbefore 0:2.2.13-12.el4_8.30:2.2.13-12.el4_8.3
Red Hat:enterprise_linux:5::clientcompat-openldapbefore 0:2.3.43_2.2.29-12.el50:2.3.43_2.2.29-12.el5
Red Hat:enterprise_linux:5::clientopenldap-clientsbefore 0:2.3.43-12.el50:2.3.43-12.el5
Red Hat:enterprise_linux:5::client_workstationopenldapbefore 0:2.3.43-12.el50:2.3.43-12.el5
Red Hat:enterprise_linux:5::client_workstationopenldap-debuginfobefore 0:2.3.43-12.el50:2.3.43-12.el5
Red Hat:enterprise_linux:5::client_workstationopenldap-develbefore 0:2.3.43-12.el50:2.3.43-12.el5
Red Hat:enterprise_linux:5::client_workstationopenldap-serversbefore 0:2.3.43-12.el50:2.3.43-12.el5
Red Hat:enterprise_linux:5::client_workstationopenldap-servers-overlaysbefore 0:2.3.43-12.el50:2.3.43-12.el5
Red Hat:enterprise_linux:5::client_workstationopenldap-servers-sqlbefore 0:2.3.43-12.el50:2.3.43-12.el5

Same product

openldap: all records

Other highest-scoring records for the same primary product.

  • CVE-2022-29155In OpenLDAP 2.x before 2.5.12 and 2.6.x before 2.6.2, a SQL injection vulnerability exists in the experimental back-sql backend to slapd, vi
    58Plan
  • CVE-2020-36228An integer underflow was discovered in OpenLDAP before 2.4.57 leading to a slapd crash in the Certificate List Exact Assertion processing, r
    55Plan
  • CVE-2020-36221An integer underflow was discovered in OpenLDAP before 2.4.57 leading to slapd crashes in the Certificate Exact Assertion processing, result
    55Plan

Published before and after this one in the same product

  • ← EarlierCVE-2008-0658Feb 13, 2008 · slapd/back-bdb/modrdn.c in the BDB backend for slapd in OpenLDAP 2.3.39 allows remote authenticated users to cause a denial of service (daem
    17Monitor
  • ← EarlierCVE-2008-2952Jul 1, 2008 · liblber/io.c in OpenLDAP 2.2.4 to 2.4.10 allows remote attackers to cause a denial of service (program termination) via crafted ASN.1 BER da
    24Monitor
  • Later →CVE-2010-0211Jul 28, 2010 · The slap_modrdn2mods function in modrdn.c in OpenLDAP 2.4.22 does not check the return value of a call to the smr_normalize function, which
    48Plan

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
debian:openldap2.4.17-2.1 · Debian:12Package registry (OSV)
debian:openldap2.32.3.30-5+etch3 · Debian:4.0Package registry (OSV)
red hat:compat-openldap0:2.3.43_2.2.29-12.el5 · Red Hat:enterprise_linux:5::clientPackage registry (OSV)
red hat:openldap0:2.3.43-12.el5 · Red Hat:enterprise_linux:5::client_workstationPackage registry (OSV)
red hat:openldap-clients0:2.3.43-12.el5 · Red Hat:enterprise_linux:5::clientPackage registry (OSV)
red hat:openldap-debuginfo0:2.3.43-12.el5 · Red Hat:enterprise_linux:5::client_workstationPackage registry (OSV)
red hat:openldap-devel0:2.3.43-12.el5 · Red Hat:enterprise_linux:5::client_workstationPackage registry (OSV)
red hat:openldap-servers0:2.3.43-12.el5 · Red Hat:enterprise_linux:5::client_workstationPackage registry (OSV)
red hat:openldap-servers-overlays0:2.3.43-12.el5 · Red Hat:enterprise_linux:5::client_workstationPackage registry (OSV)
red hat:openldap-servers-sql0:2.3.43-12.el5 · Red Hat:enterprise_linux:5::client_workstationPackage registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

    If successful

    Confidentiality
    none
    Integrity
    P · data or configuration can be modified
    Availability
    none
    Attack complexity
    M
    Confidentiality impact
    None
    Integrity impact
    P
    Availability impact
    None

    Weakness class (CWE)

    CWE-295 · Improper Certificate Validation

    CVSS vector

    AV:N/AC:M/Au:N/C:N/I:P/A:N

    nvd-primary

    Root cause

    A certificate validation error is silently swallowed instead of terminating the connection. Often, code added for a test environment makes its way into production.

    The bug in code

    The whole CWE-295 class

    A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

    Vulnerable

    kotlin
    override fun checkServerTrusted(chain: Array<X509Certificate>, type: String) {  // Left empty for the test environment}

    Fixed

    kotlin
    val client = OkHttpClient.Builder()  .certificatePinner(    CertificatePinner.Builder()      .add("api.sirius.example", "sha256/…")      .build()  ).build()

    Attack context

    MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

    ATT&CK techniques

    —

    Change log

    1. Fix✗ → ✓

    For records you follow, these changes also arrive as notifications. →

    References

    Show all references (15 more)

    Vendor advisories and official records. Exploit/PoC links are deliberately left out.

    All records