Cyber Resilience

CVE-2026-6994

Published
25 April 2026
Modified
27 April 2026
CVSS Score v4 5.3
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0023 14th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2026-6994 is a medium-severity Injection (CWE-74) vulnerability. Its CVSS base score is 5.3 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 14th 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 SI-10 (Information Input Validation) and SI-2 (Flaw Remediation) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

A05:2025 Injection

EU & UK References

Vulnerability Data

A weakness has been identified in Envoy up to 1.33.0. Affected is the function params.add of the file source/extensions/filters/http/header_mutation/header_mutation.cc of the component Query Parameter Handler. This manipulation causes injection. Remote exploitation of the attack is possible. Patch name: f8f4f1e02fdc64ecd4acf2d903208dd7285ad3a4. It…

more

is suggested to install a patch to address this issue.

CWE(s)
CWE-74CWE-707

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
Why these techniques?

Remote injection flaw in public-facing Envoy proxy directly enables exploitation of exposed applications.

Confidence: MEDIUM · MITRE ATT&CK Enterprise v19.0

Likely ATT&CK TechniquesAI

Techniques this vulnerability likely enables, inferred from its description, weakness type, and attributed-actor tradecraft. Confidence is per-technique.

T1190 Exploit Public-Facing Application Initial Accessconfidence: HIGH
Remote injection flaw in Envoy's public-facing query parameter handler directly enables exploitation of the proxy application.
attack.mitre.org →
inferred from description + CWE · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2026-2954Shared CWE-707, CWE-74
CVE-2026-7045Shared CWE-707, CWE-74
CVE-2026-9353Shared CWE-707, CWE-74
CVE-2026-9420Shared CWE-707, CWE-74
CVE-2026-3992Shared CWE-707, CWE-74
CVE-2026-9422Shared CWE-707, CWE-74
CVE-2026-11457Shared CWE-707, CWE-74
CVE-2026-5561Shared CWE-707, CWE-74
CVE-2026-10220Shared CWE-707, CWE-74
CVE-2026-29777Shared CWE-74

Affected Assets

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • SI-10 Information Input Validation
  • SI-2 Flaw Remediation
Detect
Catch it (NIST detect / respond)
  • SI-7 Software, Firmware, and Information Integrity
Harden
Shrink the surface (DISA STIG)
  • 6 hardening rules · 4 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V1.3.9
  • V1.2.1
  • V1.2.3
  • V1.2.5

Mitigating Controls (NIST 800-53 r5) AI

SI-10 Information Input Validation good match
prevent

Directly enforces validation and neutralization of untrusted query parameters before they reach params.add in the header_mutation filter, blocking CWE-74 injection.

SI-2 Flaw Remediation good match
prevent

Requires prompt application of the vendor patch (f8f4f1e) that corrects the missing neutralization logic in header_mutation.cc.

SI-7 Software, Firmware, and Information Integrity partial match
detect

Enables integrity verification of Envoy binaries and configuration to detect unauthorized changes that could introduce or exploit the injection flaw.

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.PS-06 mostly match
prevents

Secure SDLC practices directly require input validation and output encoding that prevent injection flaws.

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.8.28 Secure coding mostly match
prevents

Secure coding standards directly require proper neutralization of inputs and outputs, eliminating CWE-707.

A.8.29 Security testing in development and acceptance mostly match
detects

Security testing in development catches injection vulnerabilities before release.

A.8.15 Logging partial match
detects

Logging supports detection of injection attempts but does not prevent the weakness.

A.8.16 Monitoring activities partial match
detects

Monitoring activities can identify active injection attacks after they occur.

A.8.25 Secure development life cycle partial match
prevents

Secure development life cycle mandates input validation and output encoding that directly prevent injection flaws.

A.8.26 Application security requirements partial match
prevents

Application security requirements explicitly call for controls against injection attacks in software design.

References