Security Resilience

CVE-2026-32733

Path Traversal in Halloy ≤ 2026.4

Public PoCPath Traversal
Published
20 March 2026
Modified
23 March 2026
Patch / advisory
CVSS Score v4 8.7
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/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 0.0047 40th percentile
Risk Priority 45 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-2026-32733 is a high-severity Path Traversal (CWE-22) vulnerability in Halloy Halloy. Its CVSS base score is 8.7 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique /etc/passwd and /etc/shadow (T1003.008); ranked at the 40th 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 AC-3 (Access Enforcement) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Halloy is an IRC application written in Rust. Prior to commit 0f77b2cfc5f822517a256ea5a4b94bad8bfe38b6, the DCC receive flow did not sanitize filenames from incoming `DCC SEND` requests. A remote IRC user could send a filename with path traversal sequences like `../../.ssh/authorized_keys` and…

more

the file would be written outside the user's configured `save_directory`. With auto-accept enabled this required zero interaction from the victim. Starting with commit 0f77b2cfc5f822517a256ea5a4b94bad8bfe38b6, all identified code paths sanitize filenames through a shared `sanitize_filename` function.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1003.008 /etc/passwd and /etc/shadow Credential Access
Adversaries may attempt to dump the contents of <code>/etc/passwd</code> and <code>/etc/shadow</code> to enable offline password cracking.
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.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-50649Shared CWE-22
CVE-2023-24416Shared CWE-22
CVE-2024-9935Shared CWE-22
CVE-2025-23084Shared CWE-22
CVE-2025-32631Shared CWE-22
CVE-2025-3486Shared CWE-22
CVE-2025-34508Shared CWE-22
CVE-2026-39844Shared CWE-22
CVE-2025-6265Shared CWE-22
CVE-2023-51646Shared CWE-22

Affected Assets

halloy
halloy
≤ 2026.4

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)
  • V5.3.2

Mitigating Controls (NIST 800-53 r5) AI

Enforces the intended directory access authorizations that path traversal would otherwise bypass.

Input validation directly neutralizes special path elements before pathname construction occurs.

Least privilege reduces the impact of any unauthorized file access obtained via traversal.

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-02 partial match
blocks

Patching/maintenance can remediate known path-traversal flaws in deployed software (partial prevention of exploitability) but does nothing to stop the coding defect from being introduced in the first place.

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.

finds

Security testing in development catches path traversal via static/dynamic analysis.

prevents

Secure coding standards explicitly forbid unsafe path construction and mandate safe APIs.

References