CVE-2026-6778 | Mozilla Firefox up to 149 Playback Remote Code Execution

VDB-358475 · CVE-2026-6778 · GCVE-0-2026-6778 MOZILLA FIREFOX UP TO 149 PLAYBACK REMOTE CODE EXECUTION HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 6.0 $5k-$25k 1.16+ Summaryinfo A vulnerability was found in Mozilla Firefox up to 149. It has been classified as critical. The impacted element is an unknown function of the component Playback. The manipulation leads to an unknown weakness. This vulnerability is referenced as CVE-2026-6778. Remote exploitation of the attack is possible. No exploit is available. Upgrading the affected component is recommended. Detailsinfo A vulnerability was found in Mozilla Firefox up to 149 and classified as critical. This issue affects an unknown code block of the component Playback. The impact remains unknown. The summary by CVE is: Invalid pointer in the Audio/Video: Playback component. This vulnerability was fixed in Firefox 150. It is possible to read the advisory at bugzilla.mozilla.org. The identification of this vulnerability is CVE-2026-6778 since 04/21/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 04/21/2026). Upgrading to version 150 eliminates this vulnerability. Productinfo Type Web Browser Vendor Mozilla Name Firefox Version 149 License open-source Website Vendor: https://www.mozilla.org/ Product: https://www.mozilla.org/en-US/firefox/ 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 Vector Complexity Authentication Confidentiality Integrity Availability Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock VulDB Base Score: 🔒 VulDB Temp Score: 🔒 VulDB Reliability: 🔍 Exploitinginfo Class: Remote Code Execution CWE: Unknown CAPEC: 🔒 ATT&CK: 🔒 Physical: No Local: No Remote: Yes Availability: 🔒 Status: Not defined Price Prediction: 🔍 Current Price Estimation: 🔒 0-Day Unlock Unlock Unlock Unlock Today Unlock Unlock Unlock Unlock Threat Intelligenceinfo Interest: 🔍 Active Actors: 🔍 Active APT Groups: 🔍 Countermeasuresinfo Recommended: Upgrade Status: 🔍 0-Day Time: 🔒 Upgrade: Firefox 150 Timelineinfo 04/21/2026 Advisory disclosed 04/21/2026 +0 days CVE reserved 04/21/2026 +0 days VulDB entry created 04/21/2026 +0 days VulDB entry last update Sourcesinfo Vendor: mozilla.org Product: mozilla.org Advisory: bugzilla.mozilla.org Status: Confirmed CVE: CVE-2026-6778 (🔒) GCVE (CVE): GCVE-0-2026-6778 GCVE (VulDB): GCVE-100-358475 Entryinfo Created: 04/21/2026 16:05 Changes: 04/21/2026 16:05 (54) Complete: 🔍 Cache ID: 99:296:101 Discussion No comments yet. Languages: en. Please log in to comment. ◂ PreviousOverviewNext ▸