Google Chrome up to 148.0.7778.179 WebCodecs heap-based overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.0$5k-$25k0.00

Summaryinfo

A vulnerability identified as critical has been detected in Google Chrome. The impacted element is an unknown function of the component WebCodecs. This manipulation causes heap-based overflow. This vulnerability appears as CVE-2026-9939. The attack may be initiated remotely. There is no available exploit. You should upgrade the affected component.

Detailsinfo

A vulnerability has been found in Google Chrome and classified as critical. Affected by this vulnerability is some unknown functionality of the component WebCodecs. The manipulation with an unknown input leads to a heap-based overflow vulnerability. The CWE definition for the vulnerability is CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

Heap buffer overflow in WebCodecs in Google Chrome prior to 148.0.7778.216 allowed a remote attacker to execute arbitrary code inside a sandbox via a crafted HTML page. (Chromium security severity: High)

The advisory is shared at chromereleases.googleblog.com. This vulnerability is known as CVE-2026-9939 since 05/28/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 05/30/2026).

Upgrading to version 148.0.7778.216 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-1733). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

  • Google Chrome
  • Microsoft Edge

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Heap-based overflow
CWE: CWE-122 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Chrome 148.0.7778.216

Timelineinfo

05/28/2026 CVE reserved
05/29/2026 +1 days Advisory disclosed
05/29/2026 +0 days VulDB entry created
05/30/2026 +1 days VulDB entry last update

Sourcesinfo

Vendor: google.com
Product: google.com

Advisory: 502735
Status: Confirmed

CVE: CVE-2026-9939 (🔒)
GCVE (CVE): GCVE-0-2026-9939
GCVE (VulDB): GCVE-100-367033
CERT Bund: WID-SEC-2026-1733 - Google Chrome und Microsoft Edge: Mehrere Schwachstellen

Entryinfo

Created: 05/29/2026 09:05
Updated: 05/30/2026 15:38
Changes: 05/29/2026 09:05 (58), 05/30/2026 15:38 (7)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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