CVE-2026-74989

Exploitation

Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.

SSVC decision

• ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
• AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
• Technical ImpacttotalSuccessful exploitation gives total control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.57% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 46.8% of scored records. A rank, not a probability.

NVD base score

9.8 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

NVD analysis status

Modified. NVD last modified this record on 2026-10-28.

Red Hat severity

Moderate. Red Hat's rating for its own products, not a CVSS rating.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2026-08-18 12:23Z2 MO AGO

Last updated

2026-10-28 16:36Z1 DAY AGO

Reserved

2026-08-17

Assigning CNA

mozilla

Record state

PUBLISHED

Severity

Critical (CVSS 9.8)

CNA CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weaknesses

• CWE-119Improper Restriction of Operations within the Bounds of a Memory BufferClass

Data version

5.2

Document digest

e017c11f6e34f2793ea5f0224af8f4e4a1027d0f3d02b95f6b00a03dfa3f82a5

• bugzilla.mozilla.orgLow Severity internally found bugs fixed in Firefox 154https://bugzilla.mozilla.org/buglist.cgi?bug_id=2022257%2C2027351%2C2027380%2C2029289
• bugzilla.mozilla.orgModerate Severity internally found bugs fixed in Firefox 154https://bugzilla.mozilla.org/buglist.cgi?bug_id=2027388%2C2029750%2C2029794%2C2043298%2C2045126%2C2049810%2C2051741
• www.mozilla.orghttps://www.mozilla.org/security/advisories/mfsa2026-74/
• www.mozilla.orghttps://www.mozilla.org/security/advisories/mfsa2026-78/