CVE-2026-41709
CVE-2026-41709 is a security flaw in Broadcom VMware ESX. Attackers are using a flaw in Broadcom VMware ESX. The US Cybersecurity and Infrastructure Security Agency (CISA) added it to its catalog of flaws known to be used in attacks on 28 Oct 2026.[1]
Broadcom VMware ESX is business software or equipment. Most families won’t have it, but attackers break into it to get inside companies, and from there to what those companies hold about their customers, patients and staff. Fixed in version 5.2.4, ESXi-9.1.0.0-25370933, ESXi-9.0.2.0100-25595025 and ESXi80U3j-25429389.
Description
CISA calls it an insufficient logging in Broadcom VMware ESX. In its words: “Broadcom VMWare ESX contains an insufficient logging vulnerability that could allow a malicious actor with admin access to perform certain operations without being logged.”[1]
The underlying weakness is CWE-778, in MITRE’s list of common software weaknesses.[2]
It scores 2.7 out of 10 on the Common Vulnerability Scoring System, which rates it low, scored by the organisation that published the CVE using CVSS 3.1.[2]
Affected versions
NVD’s record lists these fixed versions: in each line, everything before the version shown is affected.[2]
| Product | Fixed in |
|---|---|
| Cloud Foundation | 5.2.4 |
| ESX | ESXi-9.1.0.0-25370933 |
| ESX | ESXi-9.0.2.0100-25595025 |
| ESX | ESXi80U3j-25429389 |
Most families won’t have Broadcom VMware ESX; it’s for whoever looks after IT at work.
Exploitation
CISA added it to its catalog of known exploited vulnerabilities on 28 Oct 2026, 90 days after it was made public. CISA lists a flaw only when it has reliable evidence of it being exploited, and gave US federal agencies until 11 Nov 2026 to fix it.[1]
FIRST’s Exploit Prediction Scoring System, which estimates how likely a flaw is to be used in attacks in the next 30 days from what it sees across the internet, puts it at under 1%. That’s in the top 48% of the flaws it scores.[4]
CISA assesses it as not automatable: each attack takes some work.
CISA doesn’t say who was attacked, or how.
Fix
Broadcom has published a fix or advice.[3] CISA’s required action: “Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes).”[1]
- Check whether you use it.Broadcom VMware ESX is business software or equipment, so most families won’t have it. If you run a business, or work from home on company equipment, ask whoever looks after your IT.
- Send this page to your IT person.Ask them to confirm it’s fixed (fixed in version 5.2.4, ESXi-9.1.0.0-25370933, ESXi-9.0.2.0100-25595025 and ESXi80U3j-25429389), or not in use. CISA gave US government agencies until 11 Nov 2026 to fix it.
- If it can’t be fixed, take it offline.CISA’s advice when there’s no fix is to stop using the product, or take it off the internet, until there is one.
You can’t fix someone else’s server, but you can watch for what follows a break-in like this: a breach notice, a password reset you didn’t ask for, or a scam message that knows things it shouldn’t. HARD watches for those for you and your family.
Timeline
| Date | Event |
|---|---|
| The flaw is made public in the National Vulnerability Database, with a severity score of 2.7.[2] | |
| CISA adds it to its catalog of flaws known to be used in attacks.[1] | |
| FIRST puts the odds of it being used in attacks in the next 30 days at under 1%.[4] | |
| CISA’s deadline for US government agencies to fix it.[1] |
See also
Other Broadcom flaws
- CVE-2026-59310, Broadcom VMware vCenter: path traversal ·
- CVE-2026-22719, Broadcom VMware Aria Operations: command injection ·
- CVE-2024-37079, Broadcom VMware vCenter Server: out-of-bounds write ·
- CVE-2025-41244, Broadcom VMware Aria Operations and VMware Tools: privilege defined with unsafe actions ·
- CVE-2025-1976, Broadcom Brocade Fabric OS: code injection ·
Added the same day
- CVE-2026-46300, Linux Kernel: missing initialization of a variable ·
Every Broadcom flaw on CISA’s list · Everything added in October 2026
References
- ^ Cybersecurity and Infrastructure Security Agency. “Broadcom VMWare ESX Insufficient Logging Vulnerability”. Known Exploited Vulnerabilities Catalog, added 28 Oct 2026.
- ^ National Institute of Standards and Technology. “CVE-2026-41709 Detail”. National Vulnerability Database, published 30 Jul 2026.
- ^ Broadcom. Advisories and fixes: support.broadcom.com.
- ^ FIRST. “Exploit Prediction Scoring System”. EPSS 0.007, percentile 52.8, 31 Oct 2026.
- CVE Program. “CVE-2026-41709”. The official CVE record.
This article is built from CISA’s catalog (version 2026.10.30), NVD’s record and FIRST’s scores, kept in HARD’s database and checked every morning. The plain English is HARD’s.