What is CVE-2023-46802?

CVE-2023-46802 is a medium-severity vulnerability in National Tax Agency E-Tax Software, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 5.5/10. Published 2023-11-06.

How severe is CVE-2023-46802?

Medium severity. CVSS v3 base score is 5.5 out of 10.

XXE in National Tax Agency E-Tax Software

CVE-2023-46802

e-Tax software Version3.0.10 and earlier improperly restricts XML external entity references (XXE) due to the configuration of the embedded XML parser. By processing a specially crafted XML file, arbitrary files on the system may be read by an attacker.

Vulnerability class: XXE (XML External Entity)

Published 2023-11-06 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.002 (8.3th percentile), scored 2026-10-04.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 8th percentile — 8.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000

Affected products

National Tax Agency E-Tax Software — versions Version3.0.10 and earlier
Nta E-Tax

Weakness classification (CWE)

CWE-611 — Improper Restriction of XML External Entity Reference (XXE)

References

www.e-tax.nta.go.jp/topics/topics_20231102.htm (Product)
jvn.jp/en/jp/JVN14762986/ (Third Party Advisory)

Frequently asked questions

What is CVE-2023-46802?: CVE-2023-46802 is a medium-severity vulnerability in National Tax Agency E-Tax Software, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 5.5/10. Published 2023-11-06.
How severe is CVE-2023-46802?: Medium severity. CVSS v3 base score is 5.5 out of 10.