Cyber Resilience

CVE-2026-16504

Exposed Creds

Exposed Creds
Published
31 July 2026
Modified
03 August 2026
CVSS Score v3.1 9.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0027 19th percentile
Risk Priority 70 floored blend · peak EPSS

Summary

CVE-2026-16504 is a critical-severity Use of Hard-coded Cryptographic Key (CWE-321) vulnerability. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Default Accounts (T1078.001); ranked at the 19th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to CM-2 (Baseline Configuration) and CM-6 (Configuration Settings) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

A04:2025 Cryptographic FailuresA07:2025 Authentication Failures

EU & UK References

Vulnerability Data

Deployment of the VPS.org one-click Zulip template deploys a hardcoded application signing key, a default database password ("zulip"), and DISABLE_HTTPS=True.

CWE(s)
CWE-321CWE-1188CWE-1393

Related Threats

MITRE ATT&CK Enterprise Techniques

T1078.001 Default Accounts Stealth
Adversaries may obtain and abuse credentials of a default account as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion.
attack.mitre.org →
T1552.004 Private Keys Credential Access
Adversaries may search for private key certificate files on compromised systems for insecurely stored credentials.
attack.mitre.org →
T1078 Valid Accounts Stealth
Adversaries may obtain and abuse credentials of existing accounts as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion.
attack.mitre.org →
T1552 Unsecured Credentials Credential Access
Adversaries may search compromised systems to find and obtain insecurely stored credentials.
attack.mitre.org →
T1552.001 Credentials In Files Credential Access
Adversaries may search local file systems and remote file shares for files containing insecurely stored credentials.
attack.mitre.org →
T1133 External Remote Services Persistence
Adversaries may leverage external-facing remote services to initially access and/or persist within a network.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-25894Shared CWE-1188, CWE-321
CVE-2026-44825Shared CWE-1188
CVE-2026-33072Shared CWE-1188
CVE-2026-36616Shared CWE-1188
CVE-2023-6448Shared CWE-1188
CVE-2026-16503Shared CWE-1188, CWE-1393
CVE-2025-48927Shared CWE-1188
CVE-2020-11532Shared CWE-1188
CVE-2025-1863Shared CWE-1188
CVE-2024-41975Shared CWE-1188

Affected Assets

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 13 hardening rules · 7 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V14.3.2
  • V6.3.2
  • V11.3.1
  • V13.2.3

Mitigating Controls (NIST 800-53 r5) AI

IA-5 Authenticator Management good match

Authenticator management requires verification of identity at initial distribution and secure handling that directly stops default passwords from remaining in use.

SC-12 Cryptographic Key Establishment and Management good match

Requiring cryptographic keys to be established and managed according to defined requirements prevents developers from embedding static unchangeable keys.

CM-2 Baseline Configuration good match

Baseline configuration directly requires documenting and maintaining secure initial settings instead of insecure defaults.

CM-6 Configuration Settings good match

Configuration settings mandate the most restrictive values be applied at initialization, eliminating reliance on insecure factory defaults.

AC-6 Least Privilege partial match

Least privilege reduces the blast radius of any insecure default permissions that remain after initialization.

SA-8 Security and Privacy Engineering Principles partial match

Security engineering principles include explicit requirements for secure defaults during resource initialization and design.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-01 full match
prevents

Credential management directly requires replacing default passwords with unique, strong credentials.

PR.PS-01 full match
prevents

Hardened baselines and configuration management directly replace insecure defaults with secure settings.

PR.PS-06 mostly match
prevents

Secure-SDLC activities such as code review and secret scanning directly prevent embedding static keys.

ID.RA-01 partial match
prevents

Vulnerability scanning will discover default-password instances, enabling remediation, yet does not itself prevent their initial use.

ID.RA-09 partial match
prevents

Pre-acquisition integrity checks can reject products known to ship with insecure defaults.

PR.AA-03 partial match
prevents

Authentication policies can enforce non-default passwords but do not address the full scope of credential lifecycle.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.5.17 Authentication information mostly match
prevents

Mandates secure handling and change of authentication secrets, directly addressing default passwords.

A.8.9 Configuration management mostly match
prevents

Mandating secure baseline templates and immediate replacement of vendor defaults directly stops systems from being deployed with insecure factory settings that attackers can exploit.

A.8.24 Use of cryptography partial match
prevents

Key-management controls that govern generation, rotation and protection of keys make the use of embedded hard-coded cryptographic keys less likely and easier to detect.

A.8.32 Change management partial match
prevents

Requiring documented specification, testing, and acceptance of changes ensures that new or modified components are not initialized with insecure default settings that would otherwise be left in production.

A.8.5 Secure authentication partial match
mitigates

Requires secure authentication mechanisms, which includes replacing or disabling default credentials.

A.5.21 Managing information security in the ICT supply chain none match
none

Requiring suppliers to document secure configuration and implemented security functions reduces the likelihood that products will be initialised with insecure default settings.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 8 (1 rule)
  • V-248823 OL 8 must not have the telnet-server package installed. prevents CWE-1188
RHEL 7 (1 rule)
  • V-204627 SNMP community strings on the Red Hat Enterprise Linux operating system must be changed from the default. prevents CWE-1188
Ubuntu 22.04 (1 rule)
  • V-260529 Ubuntu 22.04 LTS must be configured so that remote X connections are disabled, unless to fulfill documented and validated mission requirements. prevents CWE-1188
Ubuntu 24.04 (1 rule)
  • V-270708 Ubuntu 24.04 LTS must be configured so that remote X connections are disabled, unless to fulfill documented and validated mission requirements. prevents CWE-1188
Windows Server 2016 (1 rule)
  • V-224972 Active Directory Group Policy objects must have proper access control permissions. prevents CWE-1188
Windows Server 2019 (1 rule)
  • V-205741 Windows Server 2019 Active Directory Group Policy objects must have proper access control permissions. prevents CWE-1188

References