What is CVE-2023-34205?

CVE-2023-34205 is a critical-severity vulnerability in Moov Signedxml, classified under Improper Verification of Cryptographic Signature. CVSS score: 9.1/10. Published 2023-05-30.

How severe is CVE-2023-34205?

Critical severity. CVSS v3 base score is 9.1 out of 10.

Vulnerability in Moov Signedxml

CVE-2023-34205

In Moov signedxml through 1.0.0, parsing the raw XML (as received) can result in different output than parsing the canonicalized XML. Thus, signature validation can be bypassed via a Signature Wrapping attack (aka XSW).

Published 2023-05-30 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.004 (30.4th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 30th percentile — 30.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000

Affected products

Moov Signedxml — versions 1.0.0

Weakness classification (CWE)

CWE-347 — Improper Verification of Cryptographic Signature

References

github.com/moov-io/signedxml/issues/23 (Third Party Advisory, Issue Tracking)

Frequently asked questions

What is CVE-2023-34205?: CVE-2023-34205 is a critical-severity vulnerability in Moov Signedxml, classified under Improper Verification of Cryptographic Signature. CVSS score: 9.1/10. Published 2023-05-30.
How severe is CVE-2023-34205?: Critical severity. CVSS v3 base score is 9.1 out of 10.