Cyber Resilience

CVE-2021-30554

Memory Safety in Fedoraproject Fedora 33 … 34

CISA KEVActive ExploitationEUVD ExploitedMemory Safety
Published
02 July 2021
Modified
24 October 2025
KEV Added
03 November 2021
CVSS Score v3.1 8.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS Score 0.074 94th percentile
Risk Priority 90 floored blend · peak EPSS

Summary

CVE-2021-30554 is a high-severity Use After Free (CWE-416) vulnerability in Fedoraproject Fedora. Its CVSS base score is 8.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Client Execution (T1203); ranked in the top 6% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

The vulnerability is a use-after-free flaw (CWE-416) in the WebGL component of Google Chrome versions prior to 91.0.4472.114. It can result in heap corruption when processing certain inputs, as indicated by the CVSS 3.1 base score of 8.8.

A remote attacker can exploit the issue by serving a crafted HTML page to a victim who visits it in an affected browser. Successful exploitation may allow the attacker to corrupt heap memory and achieve impacts including disclosure of sensitive information, modification of data, or denial of service.

Chrome stable channel updates and downstream advisories from Fedora and Gentoo recommend upgrading to version 91.0.4472.114 or later to address the flaw. No information on observed in-the-wild exploitation is provided in the references.

EU & UK References

Vulnerability Data

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.

CWE(s)
KEV Date Added
03 November 2021

Related Threats

MITRE ATT&CK Enterprise Techniques

T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2021-21206Same product: Fedoraproject Fedoraboth on KEV
CVE-2024-4671Same product: Fedoraproject Fedoraboth on KEV
CVE-2021-30633Same product: Fedoraproject Fedoraboth on KEV
CVE-2022-3038Same product: Fedoraproject Fedoraboth on KEV
CVE-2024-2885Same product: Fedoraproject Fedora
CVE-2024-1670Same product: Fedoraproject Fedora
CVE-2024-5842Same product: Fedoraproject Fedora
CVE-2024-4368Same product: Fedoraproject Fedora
CVE-2024-5832Same product: Fedoraproject Fedora
CVE-2024-1060Same product: Fedoraproject Fedora

Affected Assets

google
chrome
≤ 91.0.4472.114
fedoraproject
fedora
33, 34

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 3 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V1.4.3

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-416

Use-after-free exploits that achieve arbitrary code execution are blocked or significantly hardened by non-executable pages and ASLR.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly incorporate memory-safety tooling and reviews that prevent most use-after-free defects.

ID.RA-01 partial match
prevents

Vulnerability identification processes can discover use-after-free issues via scanning or analysis but do not prevent their introduction.

PR.PS-02 partial match
prevents

Routine patching removes known use-after-free instances after they have been introduced in released software.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing in development can detect use-after-free bugs before release.

prevents

Secure SDLC mandates memory-safety practices that reduce use-after-free defects.

prevents

Application security requirements can specify memory-management rules that mitigate use-after-free.

prevents

Secure architecture principles include memory-safety design choices that limit use-after-free exposure.

prevents

Secure coding standards directly prescribe avoidance of use-after-free patterns.

prevents

Change-management processes help ensure memory-safety fixes are deployed consistently.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 8 (1 rule)
  • V-248592 OL 8 must clear memory when it is freed to prevent use-after-free attacks. prevents CWE-416
RHEL 8 (1 rule)
  • V-230279 RHEL 8 must clear memory when it is freed to prevent use-after-free attacks. prevents CWE-416
RHEL 9 (1 rule)
  • V-257794 RHEL 9 must clear memory when it is freed to prevent use-after-free attacks. prevents CWE-416

References