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NVD / CVE Program· CNA GitLab

CVE-2021-22212: ntpkeygen can generate keys that ntpd fails to parse.

Noroxi assessment

Priority: Monitor (action score 29/100)

  • 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: 0.52% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. Special conditions such as timing or configuration are required.
  • Fixed version: ntpsec (Alpine:v3.14) 1.2.1-r0; ntpsec (Debian:12) 1.2.0+dfsg1-4; ntpsec (openSUSE:Tumbleweed) 1.2.1-1.2.
  • Severity is disputed: the assigning authority (CNA) scores it 4.0, NVD 7.4.

Low priority for now. Upgrade to ntpsec (Alpine:v3.14) 1.2.1-r0; ntpsec (Debian:12) 1.2.0+dfsg1-4; ntpsec (openSUSE:Tumbleweed) 1.2.1-1.2 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

ntpkeygen can generate keys that ntpd fails to parse. NTPsec 1.2.0 allows ntpkeygen to generate keys with '#' characters. ntpd then either pads, shortens the key, or fails to load these keys entirely, depending on the key type and the placement of the '#'. This results in the administrator not being able to use the keys as expected or the keys are shorter than expected and easier to brute-force, possibly resulting in MITM attacks between ntp clients and ntp servers. For short AES128 keys, ntpd generates a warning that it is padding them.

HighCVSS 7.4 · v3.1—No exploit Fix available
Published
Jun 8, 2021
Updated
Jun 16, 2026
EPSS
0.5% · 44th percentile

Report tools

JSON

Action score

29

Monitor

Low priority for now.

CVSS
29 / 40 · 7.4 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.5%

CNA vs NVD score

NVD
7.4
CNA · GitLab
4.0
3.4 point gap

CVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:U/C:N/I:H/A:N

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

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

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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
ntpsecntpsec
fedoraprojectfedora

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Affected versions

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

  • fedoraproject fedora34
  • ntpsec ntpsec1.2.0

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitLab). Independent of NVD's CPE analysis and usually ahead of it.

  • NTPsec ntpsec

    • =1.2.0affected

Package-level exposure

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

EcosystemPackageAffected rangeFix
Alpine:v3.14ntpsecbefore 1.2.1-r01.2.1-r0
Debian:12ntpsecbefore 1.2.0+dfsg1-41.2.0+dfsg1-4
openSUSE:Tumbleweedntpsecbefore 1.2.1-1.21.2.1-1.2

Same product

ntpsec: all records

Other highest-scoring records for the same primary product.

Published before and after this one in the same product

  • ← EarlierCVE-2019-6442Jan 16, 2019 · An issue was discovered in NTPsec before 1.1.3.
    30Monitor
  • ← EarlierCVE-2019-6445Jan 16, 2019 · An issue was discovered in NTPsec before 1.1.3.
    30Monitor
  • Later →CVE-2023-4012Aug 7, 2023 · Incomplete Internal State Distinction in ntpsec
    30Monitor

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
alpine:ntpsec1.2.1-r0 · Alpine:v3.14Package registry (OSV)
debian:ntpsec1.2.0+dfsg1-4 · Debian:12Package registry (OSV)
opensuse:ntpsec1.2.1-1.2 · openSUSE:TumbleweedPackage 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.

No history yet (it accumulates with the daily EPSS job).

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.

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

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • Special conditions such as timing or configuration are required.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
none
Attack vector
Network
Attack complexity
High
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
None

Weakness class (CWE)

CWE-327 · Use of a Broken or Risky Cryptographic Algorithm

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

nvd-primary

Attack context

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

Change log

  1. Fix✗ → ✓

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References

Show all references (3 more)

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

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