Security Resilience

CVE-2026-56331

Info Disclosure

Public PoCInfo Disclosure
Published
30 June 2026
Modified
01 July 2026
CVSS Score v4 6.9
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/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 0.0034 26th percentile
Risk Priority 41 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2026-56331 is a medium-severity Generation of Error Message Containing Sensitive Information (CWE-209) vulnerability. Its CVSS base score is 6.9 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique System Information Discovery (T1082); ranked at the 26th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to SI-11 (Error Handling) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

A10:2025 Mishandling of Exceptional Conditions

EU & UK References

Vulnerability Data

Capgo before 12.128.2 contains improper error handling in the /private/accept_invitation endpoint that returns HTTP 500 instead of safe 4xx errors when magic_invite_string is invalid. Attackers can trigger this vulnerability using only the public key by submitting malformed magic_invite_string values to…

more

cause server errors and leak internal processing details.

CWE(s)
CWE-209

Related Threats

MITRE ATT&CK Enterprise Techniques

T1082 System Information Discovery Discovery
An adversary may attempt to get detailed information about the operating system and hardware, including version, patches, hotfixes, service packs, and architecture.
attack.mitre.org →
T1592 Gather Victim Host Information Reconnaissance
Adversaries may gather information about the victim's hosts that can be used during targeting.
attack.mitre.org →
T1592.002 Software Reconnaissance
Adversaries may gather information about the victim's host software that can be used during targeting.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-4166Shared CWE-209
CVE-2024-52896Shared CWE-209
CVE-2024-41984Shared CWE-209
CVE-2024-25037Shared CWE-209
CVE-2025-46746Shared CWE-209
CVE-2025-53803Shared CWE-209
CVE-2023-37260Shared CWE-209
CVE-2023-38017Shared CWE-209
CVE-2026-21783Shared CWE-209
CVE-2024-54366Shared CWE-209

Affected Assets

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V16.5.1

Mitigating Controls (NIST 800-53 r5) AI

SI-11 Error Handling good match

si-11 directly requires error messages to avoid revealing exploitable information about the system or its data.

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
blocks

Secure SDLC practices directly require sanitized error handling to prevent sensitive data disclosure.

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.8.29 Security testing in development and acceptance mostly match
finds

Security testing can detect error messages that leak sensitive information.

A.8.28 Secure coding partial match
prevents

Secure coding standards explicitly forbid exposing sensitive data in errors.

References