https://github.com/curl/curl

CVE-2023-28321

MEDIUM 5.9

At a glance

Source: NVD
EPSS: EPSS 1.81 % · percentile 79 (2026-10-31)
State: PUBLISHED
Published: 2023-05-26 00:00 UTC
Updated: 2025-01-15 15:54 UTC
Assigner: hackerone
NVD status: Modified

Search on…

Description

An improper certificate validation vulnerability exists in curl <v8.1.0 in the way it supports matching of wildcard patterns when listed as "Subject Alternative Name" in TLS server certificates. curl can be built to use its own name matching function for TLS rather than one provided by a TLS library. This private wildcard matching function would match IDN (International Domain Name) hosts incorrectly and could as a result accept patterns that otherwise should mismatch. IDN hostnames are converted to puny code before used for certificate checks. Puny coded names always start with `xn--` and should not be allowed to pattern match, but the wildcard check in curl could still check for `x*`, which would match even though the IDN name most likely contained nothing even resembling an `x`.

Weaknesses (CWE)

CWE-295 — Improper Certificate Validation

References

Scores

Version	Score	Vector	Scored by
CVSS 3.1	MEDIUM 5.9	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N	CISA-ADP
CVSS 3.1	MEDIUM 5.9	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N	NVD · nvd@nist.gov (Primary)
CVSS 3.1	MEDIUM 5.9	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N	NVD · 134c704f-9b21-4f2e-91b3-4a467353bcc0 (Secondary)

European references

ENISA EUVD · EUVD-2023-32028
GCVE · GCVE-0-2023-28321

CERT-FR advisories

CERTFR-2026-AVI-1385 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
CERTFR-2026-AVI-0218 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
CERTFR-2026-AVI-0199 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
CERTFR-2025-AVI-1057 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
CERTFR-2025-AVI-0969 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
CERTFR-2025-AVI-0756 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
CERTFR-2025-AVI-0622 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
CERTFR-2025-AVI-0582 — Multiples vulnérabilités dans les produits Palo Alto Networks · cert.ssi.gouv.fr
CERTFR-2024-AVI-0514 — Multiples vulnérabilités dans les produits IBM · cert.ssi.gouv.fr
CERTFR-2024-AVI-0145 — Multiples vulnérabilités dans les produits IBM · cert.ssi.gouv.fr
CERTFR-2024-AVI-0119 — Multiples vulnérabilités dans les produits Siemens · cert.ssi.gouv.fr
CERTFR-2023-AVI-0860 — Multiples vulnérabilités dans Oracle Database Server · cert.ssi.gouv.fr
CERTFR-2023-AVI-0581 — Multiples vulnérabilités dans les produits Apple · cert.ssi.gouv.fr
CERTFR-2023-AVI-0499 — Multiples vulnérabilités dans Tenable Nessus Network Monitor · cert.ssi.gouv.fr

Affected configurations (NVD CPE)

cpe:2.3:a:haxx:curl:*:*:*:*:*:*:*:* < 8.1.0
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:37:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:38:*:*:*:*:*:*:*
cpe:2.3:a:netapp:clustered_data_ontap:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:ontap_antivirus_connector:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h300s_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h500s_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h700s_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h410s_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:* ≥ 11.0 < 11.7.9
cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:* ≥ 12.0 < 12.6.8
cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:* ≥ 13.0 < 13.5

Affected products

Product	Versions
https://github.com/curl/curl	affected Fixed in 8.1.0

Sources

Source	Licence
CVE List (CVEProject cvelistV5)	CVE Program Terms of Use
EPSS (FIRST.org)	FIRST — attribution requested
ENISA EUVD	ENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)	Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feeds	Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD

🟡 https://github.com/curl/curl