CVE-2021-30554

HIGH(8.8)KEV

Google Chromium WebGL Use-After-Free Vulnerability

Description

CVE-2021-30554 is a high-severity use after free vulnerability affecting Google Chromium WebGL. Google Chromium WebGL contains a use-after-free vulnerability that allows a remote attacker to potentially exploit heap corruption via a crafted HTML page. This vulnerability could affect multiple web browsers that utilize Chromium, including Google Chrome, Microsoft Edge, and Opera. CISA has added this vulnerability to its Known Exploited Vulnerabilities (KEV) catalog, confirming active exploitation in the wild. With an EPSS score of 3.92% (88.1th percentile), this vulnerability has a notable probability of exploitation.

KEV Information

Vendor
Google
Product
Chromium WebGL
Date Added
November 3, 2021
Due Date
November 17, 2021
Required Action
Apply updates per vendor instructions.

CVSS Score

Vector String
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HOpen in Calculator
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
Exploitability Score
2.8
Impact Score
5.9

CWEs

Affected Products

VendorProductVersion
googlechrome< 91.0.4472.114
fedoraprojectfedora33; 34

Multiple CVSS Assessments

Source: [email protected](Primary)
8.8
HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0(Secondary)
8.8
HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

References

Weakness Type

CWE-416: Use After Free

Use After Free (UAF) is a vulnerability that occurs when software continues to use a pointer after the memory it references has been freed. Once memory is freed, it may be reallocated for other purposes.

Learn more: CWE-416 — Use After Free

Impact Analysis

CVE-2021-30554 carries a CVSS 3.1 score of 8.8 (HIGH), indicating a high-severity threat. The vulnerability is exploitable over the network with low attack complexity and requires no authentication, though user interaction is needed. Successful exploitation can severely compromise data confidentiality, and allow unauthorized modification of data and systems, and cause complete service disruption. Organizations running affected Chromium-based browsers face significant operational risk if this vulnerability remains unpatched.

Exploit Maturity

CVE-2021-30554 is confirmed as actively exploited through its listing in the CISA Known Exploited Vulnerabilities catalog. The EPSS score of 3.92% (88.1th percentile) indicates a measurable probability of exploitation. The vulnerability affects a widely deployed browser engine, increasing the pool of potential targets. Federal agencies were required to remediate this vulnerability by 2021-11-17 per CISA's binding operational directive.

Remediation

  1. Apply vendor patches immediately as mandated by CISA KEV: Apply updates per vendor instructions.
  2. Update all Chromium-based browsers (Google Chrome, Microsoft Edge, Opera, and others) to the latest stable version that addresses this vulnerability.
  3. If immediate patching is not possible, restrict access to untrusted web content and consider disabling the affected browser component where feasible.
  4. Monitor systems for indicators of compromise, including unusual process activity, unexpected network connections, and unauthorized configuration changes.
  5. Review security logs and conduct threat hunting to determine if the vulnerability was exploited prior to patching.

Technical Details

CVE-2021-30554 affects Google Chromium WebGL. Use after free in WebGL in Google Chrome prior to 91.0.4472.114 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page. The attack vector is network-based, meaning an attacker can exploit this vulnerability remotely by luring a victim to visit a specially crafted webpage. The CVSS score of 8.8 reflects the combination of low attack complexity, no required privileges, and high impact across confidentiality, integrity, availability.

Frequently Asked Questions

Is CVE-2021-30554 being actively exploited?

Yes. CVE-2021-30554 is listed in the CISA Known Exploited Vulnerabilities catalog, confirming active exploitation. The EPSS score of 3.92% (88.1th percentile) further indicates a measurable exploitation probability.

What products are affected by CVE-2021-30554?

CVE-2021-30554 affects Google Chromium WebGL. Since the vulnerability resides in the Chromium engine, multiple browsers that utilize Chromium may be affected, including Google Chrome, Microsoft Edge, and Opera.

How do I fix CVE-2021-30554?

Apply updates per vendor instructions. Ensure all Chromium-based browsers are updated to the latest patched versions. If patching is not immediately possible, implement network-level mitigations to limit exposure to untrusted web content.

How severe is CVE-2021-30554?

CVE-2021-30554 has a CVSS 3.1 score of 8.8 (HIGH). This is a high-severity vulnerability that requires immediate attention and remediation.

CVSS Score

8.8
HIGH(8.8)

EPSS Score

EPSS Score7.37%
EPSS Percentile93.9%

Dates

PublishedJuly 2, 2021
Last ModifiedJune 17, 2026
StatusAnalyzed
CVSS Versionv3.1

Need Help With Vulnerability Management?

Our security experts can help you prioritize and remediate vulnerabilities effectively.