CVE-2018-6406

The function ParseVP9SuperFrameIndex in common/libwebm_util.cc in libwebm through 2018-01-30 does not validate the child_frame_length data obtained from a .webm file, which allows remote attackers to cause an information leak or a denial of service (heap-based buffer over-read and later out-of-bounds write), or possibly have unspecified other impact.

Published: 2018-01-30 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2018-6406 is rated Moderate Risk (64.3/100): CVSS High severity, with medium exploitation likelihood (EPSS 2.04%). EPSS rose +1.59% over the last day, indicating growing attacker interest. Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2018-6406

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.45% 2.04% +1.59%
2 2026-04-13 0.24% 0.45% +0.21%
3 2026-03-28 — 0.24% —

Full EPSS history (14 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2018-6406

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.8 3.0 HIGH
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 5.9 [email protected]
6.8 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 8.6 6.4 [email protected]

Weakness enumeration for CVE-2018-6406

OS Trackers for CVE-2018-6406

vendor priority summary link
redhat medium — https://access.redhat.com/security/cve/CVE-2018-6406
ubuntu medium CVE-2018-6406 medium priority: Ubuntu including 2 source packages (chromium-browser, oxide-qt), 12 status rows across 6 suites (artful, bionic, cosmic, trusty, upstream, xenial): ignored 6, DNE 4, needs-triage 2. https://ubuntu.com/security/CVE-2018-6406

Affected software / configurations for CVE-2018-6406

Vendor Product Version Raw CPE
webmproject libwebm <= 2018-01-30 cpe:2.3:a:webmproject:libwebm:*:*:*:*:*:*:*:*

References for CVE-2018-6406

cvelogic Threat Intelligence