Security readout for executives and security teams
Plain-English summary
CVE-2026-2788 is a critical Mozilla vulnerability in the Audio/Video GMP component. Mozilla fixed it in Firefox 148, Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8. Organizations should prioritize updating affected Mozilla desktop software, especially where browsers or mail clients handle untrusted content.
Executive priority
High priority patching is warranted. The vulnerability is critical, affects common browser and email software, and has a maximum-impact CVSS profile. No active exploitation is confirmed in the provided sources, but delayed updates could leave high-value endpoints exposed.
Technical view
The issue is described as incorrect boundary conditions in Audio/Video: GMP and is mapped to CWE-119. The CVSS 3.1 score is 9.8 with network attack vector, low complexity, no privileges, no user interaction, and high confidentiality, integrity, and availability impact. Public details do not provide exploit mechanics.
Likely exposure
Exposure is likely on systems running Firefox, Firefox ESR, or Thunderbird before the Mozilla fixed releases. The source bundle does not provide exact vulnerable version ranges beyond the fixed versions, so inventory should compare installed versions against Mozilla advisories.
Exploitation context
The CVSS vector indicates potential remote exploitation without privileges or user interaction. However, the source bundle does not state active exploitation, and the CVE is not marked in CISA KEV. Treat as urgent because of impact, not because exploitation is confirmed.
Researcher notes
Public information is limited to the component, weakness class, severity, CVSS vector, and fixed releases. Avoid assuming exploitability details beyond the CVSS record. Bugzilla and Mozilla advisories should be monitored for additional technical disclosure or corrected version-scope information.
Mitigation direction
- Update Firefox to version 148 or the applicable fixed ESR release.
- Update Thunderbird to version 148 or 140.8 as applicable.
- Check Mozilla advisories for platform-specific update guidance.
- Prioritize managed endpoints where Firefox or Thunderbird process untrusted internet content.
Validation and detection
- Inventory installed Firefox, Firefox ESR, and Thunderbird versions.
- Confirm Firefox is 148, ESR 115.33, or ESR 140.8 where applicable.
- Confirm Thunderbird is 148 or 140.8 where applicable.
- Review endpoint management reports for failed or deferred Mozilla updates.
- Monitor Mozilla advisories for any revised affected-version details.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-119: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2026-2788 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H3.95.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
9.8CriticalVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://bugzilla.mozilla.org/show_bug.cgi?id=2014824CVE reference
- https://www.mozilla.org/security/advisories/mfsa2026-13/CVE reference
- https://www.mozilla.org/security/advisories/mfsa2026-14/CVE reference
- https://www.mozilla.org/security/advisories/mfsa2026-15/CVE reference
- https://www.mozilla.org/security/advisories/mfsa2026-16/CVE reference
- https://www.mozilla.org/security/advisories/mfsa2026-17/CVE reference
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Restriction of Operations within the Bounds of a Memory Buffer
Improper Restriction of Operations within the Bounds of a Memory Buffer represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.