CVE-2026-34610

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Source
https://cve.org/CVERecord?id=CVE-2026-34610
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-34610.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-34610
Aliases
  • GHSA-636g-jxv4-v4gr
Downstream
Related
Published
2026-04-02T17:54:53.250Z
Modified
2026-07-15T01:49:16.555496628Z
Severity
  • 5.9 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N CVSS Calculator
Summary
leancrypto: Integer truncation in X.509 name parser enables certificate identity impersonation
Details

The leancrypto library is a cryptographic library that exclusively contains only PQC-resistant cryptographic algorithms. Prior to version 1.7.1, lcx509extractnamesegment() casts sizet vlen to uint8t when storing the Common Name (CN) length. An attacker who crafts a certificate with CN = victim's CN + 256 bytes padding gets cnsize = (uint8t)(256 + N) = N, where N is the victim's CN length. The first N bytes of the attacker's CN are the victim's identity. After parsing, the attacker's certificate has an identical CN to the victim's — enabling identity impersonation in PKCS#7 verification, certificate chain matching, and code signing. This issue has been patched in version 1.7.1.

Database specific 
{
    "cwe_ids": [
        "CWE-681"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34610.json",
    "cna_assigner": "GitHub_M"
}
References

Affected packages

Git / github.com/smuellerdd/leancrypto

Affected ranges

Type
GIT
Repo
https://github.com/smuellerdd/leancrypto
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
e7fa8c87a46c5787174c18fac385aa08eecdedd1
Fixed
5cdcbe12bd6c3d6e87e969972a580b44a74c3a6a
Database specific 
{
    "cpe": "cpe:2.3:a:leancrypto:leancrypto:*:*:*:*:*:*:*:*",
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "1.7.1"
        }
    ],
    "source": [
        "CPE_RANGE",
        "REFERENCES"
    ]
}

Affected versions

v0.*
v0.10.0
v0.10.1
v0.11.0
v0.3.0
v0.4.0
v0.5.0
v0.5.1
v0.5.2
v0.5.3
v0.6.0
v0.7.0
v0.8.0
v0.9.0
v0.9.1
v0.9.2
v1.*
v1.0.0
v1.0.1
v1.1.0
v1.2.0
v1.3.0
v1.4.0
v1.5.0
v1.5.1
v1.6.0
v1.7.0

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-34610.json"