Cyber Resilience

CVE-2021-38003

Debian Linux 10.0 … 11.0

CISA KEVActive ExploitationEUVD ExploitedPublic PoC
Published
23 November 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 0.39 98th percentile
Risk Priority 90 floored blend · peak EPSS

Summary

CVE-2021-38003 is a high-severity Improper Handling of Exceptional Conditions (CWE-755) vulnerability in Debian Debian Linux. 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 2% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog; a public proof-of-concept is referenced.

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 an inappropriate implementation in the V8 JavaScript engine within Google Chrome versions prior to 95.0.4638.69. It is tracked as CVE-2021-38003 with a CVSS score of 8.8 and is associated with CWE-755, allowing potential heap corruption when a victim renders a specially crafted HTML page.

A remote attacker can exploit the flaw without authentication by serving the malicious page to a target user, who needs only to visit it in an affected browser. Successful exploitation can result in heap corruption that compromises confidentiality, integrity, and availability on the affected system.

Chrome release notes and corresponding advisories from Fedora and Debian indicate that the issue is resolved by updating to version 95.0.4638.69 or later; distribution-specific packages were made available to facilitate deployment of the patched builds.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Inappropriate implementation in V8 in Google Chrome prior to 95.0.4638.69 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.
T1489 Service Stop Impact
Adversaries may stop or disable services on a system to render those services unavailable to legitimate users.
T1499 Endpoint Denial of Service Impact
Adversaries may perform Endpoint Denial of Service (DoS) attacks to degrade or block the availability of services to users.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-2136Same product: Debian Debian Linuxboth on KEV
CVE-2021-37973Same product: Debian Debian Linuxboth on KEV
CVE-2021-37975Same product: Debian Debian Linuxboth on KEV
CVE-2021-21193Same product: Debian Debian Linuxboth on KEV
CVE-2021-21224Same product: Debian Debian Linuxboth on KEV
CVE-2021-21148Same product: Debian Debian Linuxboth on KEV
CVE-2023-7024Same product: Debian Debian Linuxboth on KEV
CVE-2021-37976Same product: Debian Debian Linuxboth on KEV
CVE-2021-21166Same product: Debian Debian Linuxboth on KEV
CVE-2021-38000Same product: Debian Debian Linuxboth on KEV

Affected Assets

google
chrome
≤ 95.0.4638.69
fedoraproject
fedora
34
debian
debian linux
10.0, 11.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 1 hardening rule · 1 OS baseline
Validate
Prove the fix (OWASP ASVS)

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-755

Provides defined handling (alert and additional actions) for the exceptional condition of audit logging failure.

addresses: CWE-755

Supplies a concrete handling action (safe mode) for exceptional conditions, mitigating risks from improper or absent handling that could allow continued attacks.

addresses: CWE-755

By preparing users for contingency scenarios, the control promotes proper handling of exceptional conditions instead of default or unsafe behaviors.

addresses: CWE-755

An updated contingency plan defines current actions for exceptional conditions, reducing the window for attackers to exploit improper handling leading to system failure.

addresses: CWE-755

Procedures ensure proper handling of exceptional conditions to support effective incident response.

addresses: CWE-755

Incident response testing confirms proper handling of exceptional conditions to limit exploit impact.

addresses: CWE-755

Gives users guidance on incident handling, reducing improper handling of exceptional conditions that could stem from exploited weaknesses.

addresses: CWE-755

Enforces structured response to exceptional conditions so the system cannot remain in an unsafe state.

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 explicitly require proper exception and error handling during design and coding.

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 and acceptance verifies correct handling of exceptional conditions.

degrades

Documented operating procedures may specify exception handling but do not guarantee implementation.

A.8.15 Logging partial match
finds

Logging captures unhandled exceptions, aiding detection but not preventing the weakness.

finds

Monitoring can surface unhandled exceptions but does not enforce proper handling.

prevents

Secure SDLC mandates exception-handling requirements and testing that directly prevent improper handling of exceptional conditions.

prevents

Application security requirements explicitly include handling of error and exceptional conditions.

References