CVE-2017-11501: NixOS 17.03 and earlier has an unintended default absence of SSL Certificate Validation for LDAP

Q: How do I fix CVE-2017-11501?

nixos: upgrade to newer than 17.03. Exact commands for each OS are on this page.

Q: Is CVE-2017-11501 being exploited?

CVE-2017-11501 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2017-11501 affect?

CVE-2017-11501 affects nixos. Severity is medium (CVSS 5.9). NixOS 17.03 and earlier has an unintended default absence of SSL Certificate Validation for LDAP. The users.ldap NixOS module implements user authentication against LDAP servers via a PAM module. It was found that if TLS is enabled to conne

Q: How urgent is CVE-2017-11501?

Priority 40/100. Remotely exploitable, no login, no user action

This month

MEDIUM 5.9REMOTEUPGRADE

CVE-2017-11501 is a medium-severity flaw (CVSS 5.9) affecting nixos. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

NixOS 17.03 and earlier has an unintended default absence of SSL Certificate Validation for LDAP. The users.ldap NixOS module implements user authentication against LDAP servers via a PAM module. It was found that if TLS is enabled to connect to the LDAP server with users.ldap.useTLS, peer verification will be unconditionally disabled in /etc/ldap.conf.

Why this priority

Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	5.9 (Medium)
Attack vector	Network (remote)
Attack complexity	High
Privileges needed	None
User interaction	None
EPSS exploit chance	0.9% (top 41%)
CISA exploited list	No
Weakness	CWE-295
Published	2017-07-20
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: nixos project

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2017-07-20 23:29 UTCPublished CVE record published
2026-06-17 01:01 UTCUpdated Record last modified

nixos project nixos UPGRADE

Affected: <= 17.03

Fixed in: newer than 17.03

Safe to downgrade to: no unaffected older release

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2017-11501?

nixos: upgrade to newer than 17.03. Exact commands for each OS are on this page.

Is CVE-2017-11501 being exploited?

CVE-2017-11501 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2017-11501 affect?

CVE-2017-11501 affects nixos. Severity is medium (CVSS 5.9). NixOS 17.03 and earlier has an unintended default absence of SSL Certificate Validation for LDAP. The users.ldap NixOS module implements user authentication against LDAP servers via a PAM module. It was found that if TLS is enabled to conne

How urgent is CVE-2017-11501?

Priority 40/100. Remotely exploitable, no login, no user action

Related CVEs

CVE-2024-12087 MEDIUM 6.5 UPGRADE MITIGATE A path traversal vulnerability exists in rsync
CVE-2024-12084 CRITICAL 9.8 DOWNGRADE MITIGATE A heap-based buffer overflow flaw was found in the rsync daemon
CVE-2017-7412 HIGH 7.8 MITIGATE NixOS 17.03 before 17.03.887 has a world-writable Docker socket, which allows local users to gain privileges b

References

← Back to latest CVEs