How severe is CVE-2018-6548?

CVE-2018-6548 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-2018-6548 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-6548?

CVE-2018-6548 affects Webmproject Libwebm. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-6548?

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-2018-6548 published?

CVE-2018-6548 was published on 2018-02-02 and last updated on 2026-06-17.

CVE-2018-6548

CVE-2018-6548 is a critical-severity vulnerability in Webmproject Libwebm 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-416.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 1% (70th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-416
Affected product: Webmproject Libwebm
Published: 2018-02-02
Last modified: 2026-06-17

Description

A use-after-free issue was discovered in libwebm through 2018-02-02. If a Vp9HeaderParser was initialized once before, its property frame_ would not be changed because of code in vp9parser::Vp9HeaderParser::SetFrame. Its frame_ could be freed while the corresponding pointer would not be updated, leading to a dangling pointer. This is related to the function OutputCluster in webm_info.cc.

Frequently asked questions

What is CVE-2018-6548?: A use-after-free issue was discovered in libwebm through 2018-02-02. If a Vp9HeaderParser was initialized once before, its property frame_ would not be changed because of code in vp9parser::Vp9HeaderParser::SetFrame. Its frame_ could be freed while the corresponding pointer would not be updated, leading to a dangling pointer. This is related to the function OutputCluster in webm_info.cc.
How severe is CVE-2018-6548?: CVE-2018-6548 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-2018-6548 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-6548?: CVE-2018-6548 affects Webmproject Libwebm. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-6548?: 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-2018-6548 published?: CVE-2018-6548 was published on 2018-02-02 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:webmproject:libwebm:*:*:*:*:*:*:*:*

More vulnerabilities in Webmproject Libwebm

CVE-2018-6406 — High (CVSS 8.8): The function ParseVP9SuperFrameIndex in common/libwebm_util.cc in libwebm through 2018-01-30 does not validate the…
CVE-2019-9746 — High (CVSS 7.5): In libwebm before 2019-03-08, a NULL pointer dereference caused by the functions OutputCluster and OutputTracks in…
CVE-2018-19212 — Medium (CVSS 6.5): In libwebm through 2018-10-03, there is an abort caused by libwebm::Webm2Pes::InitWebmParser() that will lead to a DoS…

All CVEs affecting Webmproject Libwebm →

Other CWE-416 (Use After Free) vulnerabilities

CVE-2026-13782 — Critical (CVSS 10.0): Use after free in Browser in Google Chrome prior to 150.0.7871.47 allowed a remote attacker who had compromised the…
CVE-2026-4725 — Critical (CVSS 10.0): Sandbox escape due to use-after-free in the Graphics: Canvas2D component. This vulnerability was fixed in Firefox 149…
CVE-2026-4688 — Critical (CVSS 10.0): Sandbox escape due to use-after-free in the Disability Access APIs component. This vulnerability was fixed in Firefox…
CVE-2025-24085 — Critical (CVSS 10.0): A use after free issue was addressed with improved memory management. This issue is fixed in iOS 18.3 and iPadOS 18.3,…
CVE-2024-43102 — Critical (CVSS 10.0): Concurrent removals of certain anonymous shared memory mappings by using the UMTX_SHM_DESTROY sub-request of…
CVE-2021-32495 — Critical (CVSS 10.0): Radare2 has a use-after-free vulnerability in pyc parser's get_none_object function. Attacker can read freed memory…

Browse all CWE-416 (Use After Free) vulnerabilities →