CVE-2026-42055

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.
• AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
• 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

6.54% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 93.3% of scored records. A rank, not a probability.

NVD base score

9.2 (CVSS v4.0), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

NVD analysis status

Modified. NVD last modified this record on 2026-08-25.

Red Hat severity

Important. 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

2026-06-17 14:04Z2 MO AGO

Last updated

2026-08-25 12:05Z10 DAYS AGO

Reserved

2026-06-02

Assigning CNA

f5

Record state

PUBLISHED

Severity

Critical (CVSS 9.2)

CNA CVSS vector

CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Weaknesses

• CWE-122Heap-based Buffer OverflowVariant

Data version

5.2

Document digest

d501ce1b5f49fbcc282f729e3121d01e19559f6684822a89d0ca884790036682

• my.f5.comhttps://my.f5.com/manage/s/article/K000161584vendor-advisory
• access.redhat.comhttps://access.redhat.com/security/cve/CVE-2026-42055vdb-entryx_refsource_REDHAT
• bugzilla.redhat.comRHBZ#2489866https://bugzilla.redhat.com/show_bug.cgi?id=2489866issue-trackingx_refsource_REDHAT
• security.access.redhat.comhttps://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42055.jsonx_sadp-csaf-vex
• access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:36364vendor-advisoryx_refsource_REDHAT
• access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:38847vendor-advisoryx_refsource_REDHAT
• access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:36618vendor-advisoryx_refsource_REDHAT
• access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:36331vendor-advisoryx_refsource_REDHAT
• access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:36639vendor-advisoryx_refsource_REDHAT
• access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:46836vendor-advisoryx_refsource_REDHAT
• access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:27197vendor-advisoryx_refsource_REDHAT
• access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:44481vendor-advisoryx_refsource_REDHAT
• access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:58981vendor-advisoryx_refsource_REDHAT