What is CVE-2021-3405?

CVE-2021-3405 is a medium-severity vulnerability in Matroska Libebml, classified under Out-of-bounds Write. CVSS score: 6.5/10. Published 2021-02-23.

How severe is CVE-2021-3405?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Buffer overflow in Matroska Libebml

CVE-2021-3405

A flaw was found in libebml before 1.4.2. A heap overflow bug exists in the implementation of EbmlString::ReadData and EbmlUnicodeString::ReadData in libebml.

Vulnerability class: Buffer Overflow

EPSS: 0.017 (74.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.

Affected products

Matroska Libebml
Debian Debian_linux — versions 9.0
Fedoraproject Fedora — versions 32, 33, 34
N/a Libebml — versions before 1.4.2

Weakness classification (CWE)

CWE-787 — Out-of-bounds Write

References

secalert@redhat.com (Exploit, Third Party Advisory, x_refsource_MISC, Issue Tracking)
secalert@redhat.com (x_refsource_FEDORA, vendor-advisory)
secalert@redhat.com (x_refsource_FEDORA, vendor-advisory)
secalert@redhat.com (x_refsource_FEDORA, vendor-advisory)
secalert@redhat.com (mailing-list, x_refsource_MLIST, Third Party Advisory)
secalert@redhat.com (vendor-advisory, Third Party Advisory, x_refsource_GENTOO)

Frequently asked questions

What is CVE-2021-3405?: CVE-2021-3405 is a medium-severity vulnerability in Matroska Libebml, classified under Out-of-bounds Write. CVSS score: 6.5/10. Published 2021-02-23.
How severe is CVE-2021-3405?: Medium severity. CVSS v3 base score is 6.5 out of 10.