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CVE Record

CVE-2026-33247: NATS credentials are exposed in monitoring port via command-line argv

NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Prior to versions 2.11.15 and 2.12.6, if a nats-server is run with static credentials for all clients provided via argv (the command-line), then those credentials are visible to any user who can see the monitoring port, if that too is enabled. The `/debug/vars` end-point contains an unredacted copy of argv. Versions 2.11.15 and 2.12.6 contain a fix. As a workaround, configure credentials inside a configuration file instead of via argv, and do not enable the monitoring port if using secrets in argv. Best practice remains to not expose the monitoring port to the Internet, or to untrusted network sources.

HighCVSS 7.5Not KEV-listedUpdated
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Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

Affected NATS servers can reveal client credentials through the monitoring interface when credentials were supplied on the command line. Anyone able to access that interface may obtain them without authentication or user interaction, threatening message-system confidentiality.

Executive priority

Prioritize remediation for Internet-accessible monitoring endpoints and environments using command-line credentials. Upgrade promptly or apply the documented configuration workaround. Internal-only systems without argv credentials are lower urgency but should still be verified.

Technical view

In affected nats-server versions, the monitoring `/debug/vars` endpoint returns an unredacted argv copy. Exposure requires static credentials for all clients in argv and an enabled, reachable monitoring port. Fixed releases are 2.11.15 and 2.12.6. The CVSS 3.1 score is 7.5, reflecting network-accessible, high-confidentiality impact.

Likely exposure

Exposure is limited to nats-server versions below 2.11.15 or 2.12.0-RC.1 through 2.12.5 where credentials are passed via argv and the monitoring port is accessible. Internet-facing or untrusted-network monitoring access creates the greatest risk.

Exploitation context

The bundle reports no CISA KEV listing and provides no evidence of active exploitation. Exploitation would require network access to the enabled monitoring interface under the vulnerable credential configuration, but no prior authentication or user interaction is indicated.

Researcher notes

This is an information-disclosure issue mapped to CWE-214 and CWE-215. The supplied vector is CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N. Impact stated by the sources is credential confidentiality loss; integrity and availability impact are not established. Exposure depends on both argv credential use and monitoring visibility.

Mitigation direction

  • Upgrade affected 2.11.x deployments to 2.11.15 or later.
  • Upgrade affected 2.12.x deployments to 2.12.6 or later.
  • Move static credentials from command-line arguments into a configuration file.
  • Disable the monitoring port when secrets remain in argv.
  • Restrict monitoring access from the Internet and untrusted networks.

Validation and detection

  • Inventory nats-server versions and identify instances within the affected ranges.
  • Review service definitions and startup arguments for credentials passed through argv.
  • Confirm whether monitoring is enabled and which networks can reach it.
  • After remediation, verify `/debug/vars` does not expose credentials or other argv secrets.
  • Confirm monitoring access is restricted to trusted administrative sources.
Prepared
Confidence
high
Sources
5

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cwe · low confidence lookup

CWE-214: Exact CWE lookup

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cwe · low confidence lookup

CWE-215: Exact CWE lookup

Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

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cve · low confidence lookup

CVE-2026-33247 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

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Vulnerability profileCVE Program record
Severity
High
CVSS
7.5 (3.1)
Known Exploited
No
Published

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

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

2CVSS vectors
5Timeline events
2ADP providers
9Source links

SSVC decision data

CISA-ADPCISA Coordinator
Timestamp
Version
2.0.3
Exploitation: noneAutomatable: noTechnical Impact: total

CVSS vector scores

2 official scores

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
7.5CVSS 3.1HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N3.93.6redhat-SADP
7.4CVSS 3.1HighCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N2.25.2GitHub_M

Vulnerability scoring details

Base CVSS 3.1 score

7.5High
CVSS 3.1 vector shape for CVE-2026-33247Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

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

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  2. ADP timelineredhat-SADP

    Made public.

  3. CVE publishedCVE Program

    The CVE record was published.

  4. ADP timelineredhat-SADP

    Reported to Red Hat.

  5. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

ADP provider summaries

CISA-ADPCISA ADP Vulnrichment
other:ssvc
redhat-SADPgithub.com/nats-io/nats-server: NATS-Server: Information disclosure of credentials via monitoring port and command-line arguments
other:Red Hat severity ratingcvssV3_1
  • 2026-03-25T21:02:07.985Z: Reported to Red Hat.
  • 2026-03-25T20:02:18.868Z: Made public.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
nats-ionats-server< 2.11.15, >= 2.12.0-RC.1, < 2.12.6Listed
Weakness

CWE details

CWE-214CWE-215

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.

CWE-214 · source CWE mapping

Invocation of Process Using Visible Sensitive Information

Invocation of Process Using Visible Sensitive Information represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

Open CWE intelligenceSame-CWE CVEs
CWE-215 · source CWE mapping

Insertion of Sensitive Information Into Debugging Code

Insertion of Sensitive Information Into Debugging Code represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

Open CWE intelligenceSame-CWE CVEs