High 7.5Published Oct 22, 2019

CVE-2019-12290GNU libidn2 before 2.2.0 fails to perform the roundtrip checks specified in RFC3490 Section 4.2 when converting A-labels to U-labels.

Updated under an hour ago (Oct 26, 2026, 4:10 PM ET)

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It affects Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP and 3 other products. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP

Exploited in the last 30 days

GNU libidn2 before 2.2.0 fails to perform the roundtrip checks specified in RFC3490 Section 4.2 when converting A-labels to U-labels. This makes it possible in some circumstances for one domain to impersonate another. By creating a malicious domain that matches a target domain except for the inclusion of certain punycoded Unicode characters (that would be discarded when converted first to a Unicode label and then back to an ASCII label), arbitrary domains can be impersonated.

CVSS: 7.5 HIGH (v3.1, NVD)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Weakness (CWE): Not given
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: mitre
NVD analysis: Modified
Record last updated: Oct 14, 2026
First seen by InfoSec Signals: Oct 14, 2026

Affected products

Affected products

Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP siemens:simatic_s7_1500_cpu_1518_4_pn_dp_mfp (from the name)	from V3.1.0 before V3.1.5	CISA ADP
Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP siemens:simatic_s7_1500_cpu_1518f_4_pn_dp_mfp (from the name)	from V3.1.0 before V3.1.5	CISA ADP
Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP siemens:siplus_s7_1500_cpu_1518_4_pn_dp_mfp (from the name)	from V3.1.0 before V3.1.5	CISA ADP
gnu libidn2 gnu:libidn2	before 2.2.0	NVD

References

References

https://gitlab.com/libidn/libidn2/merge_requests/71	x-refsource-misc, patch, third-party-advisory
https://gitlab.com/libidn/libidn2/commit/241e8f486134793cb0f4a5b0e5817a97883401f5	x-refsource-misc, patch, third-party-advisory
https://gitlab.com/libidn/libidn2/commit/614117ef6e4c60e1950d742e3edf0a0ef8d389de	x-refsource-confirm, third-party-advisory
https://usn.ubuntu.com/4168-1/	vendor-advisory, x-refsource-ubuntu
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/U6ZXL2RDNQRAHCMKWPOMJFKYJ344X4HL/	vendor-advisory, x-refsource-fedora
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3UFT76Y7OSGPZV3EBEHD6ISVUM3DLARM/	vendor-advisory, x-refsource-fedora
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KXDKYWFV6N2HHVSE67FFDM7G3FEL2ZNE/	vendor-advisory, x-refsource-fedora
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RSI4TI2JTQWQ3YEUX5X36GTVGKO4QKZ5/	vendor-advisory, x-refsource-fedora
http://lists.opensuse.org/opensuse-security-announce/2019-12/msg00009.html	vendor-advisory, x-refsource-suse
http://lists.opensuse.org/opensuse-security-announce/2019-12/msg00008.html	vendor-advisory, x-refsource-suse
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The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.