Google Chromium V8 Out of Bounds Write Vulnerability
Google · Chromium V8
8.8HighCVSS 3.1
Recommended action
Protect now
CISA confirms exploitation in the wild and lists 2026-09-23 as the remediation due date.
Fix not verified
Direct vendor intelligence
Authoritative vendor CSAF and VEX advisories
Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.
1 current
CVE-2026-87491 · CSAF 2.0 · revision 3 · finalRed Hat Product Securitychromium-browser: Chromium-browser: Arbitrary code execution via out-of-bounds write in V8
1 known not affected
The vendor explicitly states that these products are not affected by this CVE.
All currently supported Red Hat products
Summary
A flaw was found in chromium-browser. A remote attacker could exploit an out-of-bounds write vulnerability in the V8 JavaScript engine by crafting a malicious HTML page. This could allow the attacker to execute arbitrary code within the browser's sandbox environment.
Remediation
No remediation text is recorded.
Optional official sources
National CERT insights ?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.
Select the national-authority views to include. The exact source language is shown on each matched advisory. Your choice is remembered on this device and encoded in the shareable URL.
Official European source
ENISA European Vulnerability Database
Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.
1 current
ENISA EUVD identifier
EUVD-2026-74529
CISA KEV mirrored by ENISA
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)
EUVD state
Present in the current official mapping
Known exploitation
Recorded by ENISA since 9 Sept 2026. Evidence sources: cisa_kev.
ENISA score
8.8 · CVSS 3.1
Advisory evidence
1 linked advisory record
Explicit mitigation evidence
Only statements that explicitly mention a fix, patch, update, workaround or mitigation are shown here.
csaf_ncscnl · NCSC-2026-0354Kwetsbaarheid verholpen in Google Chrome
Recommended actionProtect now
CISA confirms exploitation in the wild and lists 2026-09-23 as the remediation due date.
Fix not verified
01
What, why and how
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.
What
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.
Why
A bounds error lets data be written beyond the intended memory region, potentially corrupting control data.
How
An attacker operating through a network path may attempt exploitation without authentication after a user interaction. If successful, the issue may execute code or commands in the affected security context.
What
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.
Why
A bounds error lets data be written beyond the intended memory region, potentially corrupting control data.
How
An attacker operating through a network path may attempt exploitation without authentication after a user interaction. If successful, the issue may execute code or commands in the affected security context.
02
Exploit reality and attack path
CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.
Observed exploitation ?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.Confirmed in the wild
CISA added this CVE to its Known Exploited Vulnerabilities catalogue on 2026-09-09.
Public PoC / exploit material ?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.None recorded
No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.
Likely attack path
a network path → Out-of-bounds Write → execute code or commands in the affected security context
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
Required interaction required
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness ?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-787: Out-of-bounds Write. The product writes data past the end, or before the beginning, of the intended buffer.
CVSS vector ?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.
AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UIRequiredUser interaction: Another user must perform an action for exploitation to succeed.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major loss.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land
After compromise, an attacker may use built-in shells, scripting engines, scheduled tasks and native network utilities for discovery, persistence or movement. This is a plausible LoTL path, not evidence that it has occurred for every attack.
Only matched European and national findings are included. Language selectors and unavailable sources are omitted.
ENISA EUVD · EUVD-2026-74529Known-exploited evidence recorded
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)
Official EUVD record ↗BSI · German · WID-SEC-2026-3238Google Chrome: Mehrere Schwachstellen ermöglichen nicht spezifizierten Angriff
Ein Angreifer kann mehrere Schwachstellen in Google Chrome ausnutzen, um nicht näher spezifizierte Angriffe durchzuführen, darunter möglicherweise die Ausführung von beliebigem Code, die Umgehung von Sicherheitsmaßnahmen, die Ausweitung von Berechtigungen, die Offenlegung sensibler Informationen, die Durchführung von XSS-Angriffen oder das Auslösen eines Denial-of-Service-Zustands.
Official advisory ↗CERT-FR · French · CERTFR-2026-AVI-1139Multiples vulnérabilités dans Google Chrome
ate de la première version 09 septembre 2026
Date de la dernière version 09 septembre 2026
Source(s)
Bulletin de sécurité Google Chrome du 08 septembre 2026
Une gestion de version détaillée se trouve à la fin de ce document.
Risque
Non spécifié par l'éditeur
Systèmes affectés
Chrome versions antérieures à 153.0.8010.36 pour Linux
Chrome versions antérieures à 153.0.8010.36 pour Windows
Chrome versions antérieures à 153.0.8010.37 pour Mac
Résumé
De multiples vulnérabilités ont été découvertes dans Google Chrome. Elles permettent à un attaquant de provoquer un problème de sécurité non spécifié par l'éditeur.
Google indique que la vulnérabilité CVE-2026-87491 est activement exploitée.
Solutions
Se référer au bulletin de sécurité de l'éditeur pour l'obtention des correctifs (cf. section Documentation).
Documentation
Bulletin de sécurité Google Chrome du 08 septembre 2026
https://chromereleases.googleblog.com/2026/09/stable-channel-update-for-desktop_0808145027.html
Référence CVE CVE-2026-87429
https://www.cve.org/CVERecord?id=CVE-2026-87429
Référence CVE CVE-2026-87430
https://www.cve.org/CVERecord?id=CVE-2026-87430
Référence CVE CVE-2026-87431
https://www.cve.org/CVERecord?id=CVE-2026-87431
Référence CVE CVE-2026-87432
https://www.cve.org/CVERecord?id=CVE-2026-87432
Référence CVE CVE-2026-87433
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A program a puffer határa előtt vagy után ír adatokat a memóriába.
Official advisory ↗CSIRT Italia · Italian · risolte-vulnerabilita-in-google-chrome-72Risolte vulnerabilità in Google Chrome
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Sintesi
Google ha rilasciato un aggiornamento per il browser Chrome al fine di correggere 230 nuove vulnerabilità di sicurezza, di cui 5 con gravità “critica” e 41 con gravità “alta”. Tra queste si segnala la CVE-2026-87491 che risulta attivamente sfruttata in rete.
Tipologia
Arbitrary Code Execution
Security Restrictions Bypass
Information Disclosure
Descrizione e potenziali impatti
In dettaglio, la vulnerabilità identificata tramite la CVE-2026-87491 - di tipo "Out-of-bounds write" e classificata di gravità "media" - risiede nel componente V8 , l'engine open source di Google deputato all'esecuzione di codice JavaScript e WebAssembly all'interno del browser, in cui le dimensioni degli indici o dei puntatori sono sottoposte a una non adeguata convalida. In particolare, un utente malintenzionato potrebbe ottenere la scrittura di dati al di fuori del buffer prepo
Official advisory ↗NCSC-NL · Dutch · NCSC-2026-0354Kwetsbaarheid verholpen in Google Chrome
Google meldt dat de kwetsbaarheid met kenmerk CVE-2026-87491 actief wordt misbruikt. Het betreft een out-of-bounds write in de V8-engine van Google Chrome, die voorkomt in versies vóór 153.0.8010.36. Een kwaadwillende kan een speciaal vervaardigde HTML-pagina gebruiken om de kwetsbaarheid te activeren en binnen de sandbox willekeurige code uit te voeren. De kwetsbaarheid wordt veroorzaakt door onjuiste bounds checking in het geheugenbeheer van V8, wat kan leiden tot geheugenbeschadiging. Succesvol misbruik kan daarnaast leiden tot toegang tot gegevens buiten de toegewezen geheugenbuffer, waardoor gevoelige informatie kan worden buitgemaakt of de browser kan crashen.
Operational remediation based on structured source evidence.
Status ?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Fix not verified
Affected
Chrome: 153.0.8010.36 < 153.0.8010.36
Fixed
No fixed version is explicitly recorded in the structured CVE data.
Action
No verified patch reference is present in the current structured sources. Check the vendor advisory before making a change.
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04
Evidence and provenance
Published 9 Sept 2026 · Last source change 10 Sept 2026, 03:55 UTC · CWE-787 · Out-of-bounds Write
CVE recordCVE.org · 5.2
CVSS sourceCISA ADP
EPSS source ?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.FIRST · tracked since 2026-09-09
European sourceENISA EUVD · EUVD-2026-74529
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD enriched
Core structured fields are present and their contributing authorities are shown above.
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
CVE-2026-87491: Google Chromium V8 Out of Bounds Write Vulnerability | BlackTree
