What is CVE-2023-28118?

CVE-2023-28118 is a high-severity vulnerability in Charleskorn Kaml, classified under Improper Restriction of Recursive Entity References in DTDs (XML Entity Expansion). CVSS score: 7.5/10. Published 2023-03-20.

How severe is CVE-2023-28118?

High severity. CVSS v3 base score is 7.5 out of 10.

XXE in Charleskorn Kaml

CVE-2023-28118

kaml provides YAML support for kotlinx.serialization. Prior to version 0.53.0, applications that use kaml to parse untrusted input containing anchors and aliases may consume excessive memory and crash. Version 0.53.0 and later default to refusing to parse YAML documents containing anchors and aliases. There are no known workarounds.

Published 2023-03-20 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.010 (60.6th percentile), scored 2026-10-01.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 61st percentile — 60.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.010 · newest: 0.010 · change: 0.000

Affected products

Charleskorn Kaml — versions < 0.53.0
Kaml Project

Weakness classification (CWE)

CWE-776 — Improper Restriction of Recursive Entity References in DTDs (XML Entity Expansion)

References

github.com/charleskorn/kaml/security/advisories/GHSA-c24f-2j3g-rg48 (Vendor Advisory)
github.com/charleskorn/kaml/commit/5f82a2d7e00bfc307afca05d1dc4d7c50593531a (Patch)
github.com/charleskorn/kaml/releases/tag/0.53.0 (Release Notes)

Frequently asked questions

What is CVE-2023-28118?: CVE-2023-28118 is a high-severity vulnerability in Charleskorn Kaml, classified under Improper Restriction of Recursive Entity References in DTDs (XML Entity Expansion). CVSS score: 7.5/10. Published 2023-03-20.
How severe is CVE-2023-28118?: High severity. CVSS v3 base score is 7.5 out of 10.