Vulnerability record · CVE-2014-0195 · published 5 June 2014
CVE-2014-0195: OpenSSL DTLS ClientHello fragment length buffer overflow
OOpenssl · Openssl
OpenSSL's dtls1_reassemble_fragment function in d1_both.c fails to properly validate fragment lengths in DTLS ClientHello messages. A long non-initial fragment triggers a buffer overflow, allowing remote code execution or denial of service. The flaw affects OpenSSL before 0.9.8za, 1.0.0 before 1.0.0m, and 1.0.1 before 1.0.1h, and is also present in downstream products such as MariaDB, openSUSE and Fedora.
Description
The dtls1_reassemble_fragment function in d1_both.c in OpenSSL before 0.9.8za, 1.0.0 before 1.0.0m, and 1.0.1 before 1.0.1h does not properly validate fragment lengths in DTLS ClientHello messages, which allows remote attackers to execute arbitrary code or cause a denial of service (buffer overflow and application crash) via a long non-initial fragment.
AV:N/AC:M/Au:N/C:P/I:P/A:P
Automated analysis
high priorityRemote code execution and denial of service with no authentication, and an EPSS score near 1.0 despite not being in KEV.
What it is
OpenSSL's dtls1_reassemble_fragment function in d1_both.c fails to properly validate fragment lengths in DTLS ClientHello messages. A long non-initial fragment triggers a buffer overflow, allowing remote code execution or denial of service. The flaw affects OpenSSL before 0.9.8za, 1.0.0 before 1.0.0m, and 1.0.1 before 1.0.1h, and is also present in downstream products such as MariaDB, openSUSE and Fedora.
Impact
A remote attacker can execute arbitrary code in the context of the affected service or crash it, causing a denial of service.
Attack surface
Reachable over the network via DTLS traffic; no authentication is required, but the CVSS vector indicates medium attack complexity and no user interaction.
Exploitation
Not listed in CISA KEV, but EPSS is extremely high (0.99977, 99.979th percentile), indicating a very high likelihood of exploitation activity; references are advisories and mailing lists, with no public exploit tag.
What to do
- Upgrade OpenSSL to 0.9.8za, 1.0.0m, 1.0.1h or later, or apply the vendor patch for your distribution.
- Update downstream packages (MariaDB, openSUSE, Fedora) that bundle or link the vulnerable OpenSSL version.
- Disable DTLS on services that do not require it, or restrict DTLS endpoints to trusted networks.
- Monitor vendor advisories for backported fixes if immediate upgrade is not possible.
Detection
- Inspect DTLS traffic for unusually long non-initial ClientHello fragments or malformed fragment lengths.
- Monitor service logs for crashes or restarts in processes using DTLS (e.g., OpenSSL-based servers).
- Use network IDS signatures that detect CVE-2014-0195 DTLS fragment anomalies.
- Check running OpenSSL versions against the fixed releases (0.9.8za, 1.0.0m, 1.0.1h).
This assessment is produced automatically and is not human-reviewed. Verify against the vendor advisory before acting on it.
Affected products
5 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
Track CVE-2014-0195 inside VULONE
Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.
Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2014-0195), CISA KEV, FIRST EPSS (scores of 2026-09-16). This page is refreshed as NVD updates the record.
