What is CVE-2021-38003?
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.
The record classifies CVE-2021-38003 under weakness class CWE-755. Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs a user to take an action first, and has high impact on confidentiality, integrity, availability. 4 affected-product entries are recorded, across 3 vendors, listed below. The identifier was first published 1804 days ago.
Severity and exploitation probability
- CVSS v3.1 base score
- 8.8 — HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - EPSS (FIRST)
- 38.5% probability of exploitation in the next 30 days, higher than 98.5% of all scored CVEs
- CISA KEV
- Listed since 2021-11-03, federal remediation deadline 2021-11-17
- Threadlinqs priority
- 9/10 — CISA KEV-listed, which Threadlinqs floors at 9
- Published
- 2021-11-23, last modified 2025-10-21
Is CVE-2021-38003 being exploited?
CISA added CVE-2021-38003 to the Known Exploited Vulnerabilities catalog on 2021-11-03, which means the agency holds evidence of exploitation in the wild; US federal civilian agencies had to remediate it by 2021-11-17 under BOD 22-01. Weaponised exploit code for CVE-2021-38003 is publicly available. 2 public proof-of-concept repositories are tracked for this identifier. It currently carries a trending score of 53 in the Threadlinqs vulnerability feed.
- SpiralBL0CK/Chrome-V8-RCE-CVE-2021-38003 (github)
- trickest/cve (trickest)
Affected products and versions
- Google: Chrome
- Fedoraproject: Fedora 34
- Debian: Linux 10.0, Linux 11.0
How to fix CVE-2021-38003
The record marks a vendor fix as available for CVE-2021-38003. Vendor advisory: https://chromereleases.googleblog.com/2021/10/stable-channel-update-for-desktop_28.html. Because CVE-2021-38003 is KEV-listed, US federal civilian agencies were required to apply the vendor fix, or stop using the product, by 2021-11-17. Apply the vendor fix referenced above to every affected product listed in this record, then confirm the running version against the vendor advisory.
Threat activity tracking CVE-2021-38003
3 tracked threats in the Threadlinqs corpus reference CVE-2021-38003, either in the campaign’s CVE list or as an indicator on the campaign record.
- September 2026 CVE Landscape: 94 high-impact vulnerabilities, NetScaler zero-days CVE-2026-88771/CVE-2026-88772, AI-agent-assisted exploitation — CRITICAL · 2026-10-14
- CVE-2026-51990: One-Click RCE in Tencent Sogou Input Method Exploited by UNC3569 to Deploy GrayRabbit Malware — CRITICAL · 2026-09-13
- Hack-for-Hire Espionage Campaign Targeting MENA Civil Society via Predator/Intellexa Mercenary Spyware — HIGH · 2026-04-08
Sources
Enriched from CVE.org, FIRST EPSS, CISA KEV, public proof-of-concept repositories. Last verified by Threadlinqs on .