CVE-2019-18224
CVE-2019-18224 is a critical-severity vulnerability in Gnu Libidn2 with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.
Key facts
- Severity: Critical (CVSS 3.x base score 9.8)
- CVSS v2: 7.5
- EPSS exploit prediction: 4% (88th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-787
- Affected product: Gnu Libidn2
- Published:
- Last modified:
Description
idn2_to_ascii_4i in lib/lookup.c in GNU libidn2 before 2.1.1 has a heap-based buffer overflow via a long domain string.
Frequently asked questions
- What is CVE-2019-18224?
- idn2_to_ascii_4i in lib/lookup.c in GNU libidn2 before 2.1.1 has a heap-based buffer overflow via a long domain string.
- How severe is CVE-2019-18224?
- CVE-2019-18224 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2019-18224 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2019-18224?
- CVE-2019-18224 affects Gnu Libidn2. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2019-18224?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2019-18224 published?
- CVE-2019-18224 was published on 2019-10-21 and last updated on 2026-06-17.
References
- http://lists.opensuse.org/opensuse-security-announce/2019-12/msg00008.html
- http://lists.opensuse.org/opensuse-security-announce/2019-12/msg00009.html
- https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=12420
- https://github.com/libidn/libidn2/commit/e4d1558aa2c1c04a05066ee8600f37603890ba8c
- https://github.com/libidn/libidn2/compare/libidn2-2.1.0...libidn2-2.1.1
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JDQVQ2XPV5BTZUFINT7AFJSKNNBVURNJ/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MINU5RKDFE6TKAFY5DRFN3WSFDS4DYVS/
- https://seclists.org/bugtraq/2020/Feb/4
- https://security.gentoo.org/glsa/202003-63
- https://usn.ubuntu.com/4168-1/
- https://www.debian.org/security/2020/dsa-4613
Affected products (1)
- cpe:2.3:a:gnu:libidn2:*:*:*:*:*:*:*:*
More vulnerabilities in Gnu Libidn2
- CVE-2017-14062 — Critical (CVSS 9.8): Integer overflow in the decode_digit function in puny_decode.c in Libidn2 before 2.0.4 allows remote attackers to cause…
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