CVE-2026-87491
Google Chromium V8: Out of Bounds Write
As of , CVE-2026-87491 in Google Chromium V8 is on CISA's list of exploited vulnerabilities: CISA listed it on . Our patch-first group: Patch soon.
- Exploited
- Yes: CISA listed it on 9 September 2026
- US federal deadline
- 23 September 202614 days after CISA listed it. US federal civilian agencies must fix it by then.
- Used in ransomware campaigns
- Not known to CISA
- EPSS score
- 0.03Higher than 87% of the CVEs EPSS scores. EPSS estimates the chance of exploitation activity in the next 30 days.
- Public exploit
- None foundNeither Metasploit nor Exploit-DB lists one.
- Fix
- Vendor advice: chromereleases.googleblog.comLinks below, from CISA's entry.
What CISA says to do
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
CISA's required action
What the flaw is
Google Chromium V8 contains an out of bounds write vulnerability that allows a remote attacker to execute arbitrary code inside the sandbox via a crafted HTML page. This vulnerability could affect multiple web browsers that utilize Chromium, including, but not limited to, Google Chrome, Microsoft Edge, and Opera.
CISA's description
Out of bounds write in V8 in Google Chrome prior to 153.0.8010.36 allowed a remote attacker to execute arbitrary code inside the sandbox via a crafted HTML page. (Chromium security severity: Medium)
The CVE record's description, from Chrome
- CVE published
- 9 September 2026
- Assigned by
- Chrome
- CVSS
- 8.8 High (CVSS 3.1, from CISA-ADP)
- CWE-787
- Out-of-bounds Write
- CISA SSVC, exploitation
- active
- CISA SSVC, automatable
- no
- CISA SSVC, technical impact
- total
Timeline
- The CVE record was published.
- CISA added it to its list of exploited vulnerabilities.
- The US federal deadline to fix it.
Chromium V8: other exploited entries
| Vulnerability | Product | Our group | Listed | Deadline | EPSS |
|---|---|---|---|---|---|
| CVE-2018-17463Remote Code Execution | Google Chromium V8 | Patch this weekMetasploit module; EPSS 0.85; verified Exploit-DB entry | 0.85 | ||
| CVE-2019-5825Out-of-Bounds Write | Google Chromium V8 | Patch this weekMetasploit module; EPSS 0.56; verified Exploit-DB entry | 0.56 | ||
| CVE-2020-6418Type Confusion | Google Chromium V8 | Patch this weekMetasploit module; EPSS 0.79; verified Exploit-DB entry | 0.79 | ||
| CVE-2021-21220Improper Input Validation | Google Chromium V8 | Patch this weekMetasploit module; EPSS 0.70 | 0.70 | ||
| CVE-2018-6065Integer Overflow | Google Chromium V8 | Patch this weekEPSS 0.60; verified Exploit-DB entry | 0.60 | ||
| CVE-2021-21224Type Confusion | Google Chromium V8 | Patch this weekEPSS 0.84 | 0.84 | ||
| CVE-2021-30551Type Confusion | Google Chromium V8 | Patch this weekEPSS 0.65 | 0.65 | ||
| CVE-2021-30632Out-of-Bounds Write | Google Chromium V8 | Patch this weekEPSS 0.63 | 0.63 | ||
| CVE-2026-85046Type Confusion | Google Chromium V8 | Patch soon | 0.49 | ||
| CVE-2023-4762Type Confusion | Google Chromium V8 | Patch soon | 0.41 |
Read further
- CVE recordcve.org
- NVD entrynvd.nist.gov
- CISA's catalogcisa.gov
- EPSS for this CVEapi.first.org