Published:2023/11/10  Last Updated:2023/11/10

JVN#86156389
Remarshal unlimitedly expanding YAML alias nodes

Overview

Remarshal expands YAML alias nodes unlimitedly, vulnerable to Billion-laughs Attack.

Products Affected

  • Remarshal versions prior to v0.17.1

Description

Remarshal provided by Remarshal Project expands YAML alias nodes unlimitedly (CWE-674), hence Remarshal is vulnerable to Billion Laughs Attack.

Impact

Processing untrusted YAML files may cause a denial-of-service (DoS) condition.

Solution

Update the Software
Update to the latest version according to the information provided by the developer.
The developer has released the version listed below that addresses the vulnerability.

  • Remarshal v0.17.1

Vendor Status

Vendor Link
Remarshal Project v0.17.1
fix(yaml): limit maximum nodes

References

  1. yaml-spec
    issue#45: Current version of the YAML specification could leave implementions open to Denial of Service Attacks

JPCERT/CC Addendum

Vulnerability Analysis by JPCERT/CC

CVSS v3 CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Base Score: 5.5
Attack Vector(AV) Physical (P) Local (L) Adjacent (A) Network (N)
Attack Complexity(AC) High (H) Low (L)
Privileges Required(PR) High (H) Low (L) None (N)
User Interaction(UI) Required (R) None (N)
Scope(S) Unchanged (U) Changed (C)
Confidentiality Impact(C) None (N) Low (L) High (H)
Integrity Impact(I) None (N) Low (L) High (H)
Availability Impact(A) None (N) Low (L) High (H)
CVSS v2 AV:N/AC:M/Au:N/C:N/I:N/A:P
Base Score: 4.3
Access Vector(AV) Local (L) Adjacent Network (A) Network (N)
Access Complexity(AC) High (H) Medium (M) Low (L)
Authentication(Au) Multiple (M) Single (S) None (N)
Confidentiality Impact(C) None (N) Partial (P) Complete (C)
Integrity Impact(I) None (N) Partial (P) Complete (C)
Availability Impact(A) None (N) Partial (P) Complete (C)

Comment

This analysis assumes that a victim user is directed to process some crafted YAML file.

Credit

Taichi Kotake of Sterra Security Co.,Ltd. / Akatsuki Games Inc. reported this vulnerability to IPA.
JPCERT/CC coordinated with the developer under Information Security Early Warning Partnership.

Other Information

JPCERT Alert
JPCERT Reports
CERT Advisory
CPNI Advisory
TRnotes
CVE CVE-2023-47163
JVN iPedia JVNDB-2023-000111