CVE-2026-98929

UNRATEDCVSS · not yet scored

Also known asEUVD-2026-108899 (ENISA EUVD) · GHSA-83cv-x2cm-qpmg (GitHub Security Advisories)Source: ENISA EUVD

—
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • No CVSS published and no exploitation signals yet
CISA-KEV: Not listedEPSS PROB: 0.2%CVSS v2: —Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

In the Linux kernel, the following vulnerability has been resolved:

macsec: initialize SecY before registering the netdevice

Creating a MACsec device with MAC offload over an LRO-capable lower device triggers a warning in rtmsg_ifinfo_build_skb() when IPv4 forwarding is enabled by default.

register_netdevice() invokes inetdev_init(), which disables LRO and emits a NETDEV_FEAT_CHANGE notification. This reaches macsec_fill_info() before macsec_add_dev() initializes the SecY. key_len is still zero, so macsec_fill_info() returns -EMSGSIZE and trips the WARN_ON in rtmsg_ifinfo_build_skb(), even though the skb has enough space.

Even without the warning, notifications during registration can report uninitialized SecY attributes, including the SCI. This ordering has existed since the driver was introduced.

Initialize the SecY and apply the new-link attributes before registration. Move MAC address inheritance into macsec_newlink() so the SCI can also be initialized before registration-time notifications report it. Move the per-CPU statistics and metadata destination allocation into ndo_init(), and release partial allocations on failure.

CVSS v3
—
EchelonGraph score
Not yet assessedNo source has published severity data for this CVE yet — no CVSS score from NVD or a CNA, no GitHub advisory, and it is not in CISA KEV. This is not a rating of zero; we cannot assess it yet.
EG Score
—
EG Risk
—
EPSS PROB
0.2%
EPSS %ILE
5th
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

EG Severity
Not assessed: no CVSS publishedA missing CVSS is not a severity of zero.
EG Likelihood
0.2% within 30 daysSource: FIRST EPSS. FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
No SSVC decision: EchelonGraph has not assessed this CVECISA BOD 26-04: 14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source, and whom BOD 26-04 binds: the BOD 26-04 block below.

BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). Where an input reads “CISA's BOD 26-04 default”, no one has published it for this CVE, and CISA's implementation guidance says: “If “Automatable” and “Technical Impact” information items about a CVE ID are not available and the CVE ID is not in the KEV Catalog, CISA will treat its values as “no” and “total,” respectively, until CISA or a third party provides metadata about the CVE ID. CISA will always provide the Vulnrichment data for a CVE ID listed in the KEV Catalog.” Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

October 23, 2026

Last Modified

October 23, 2026

Vendor Advisories for CVE-2026-98929(2)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(1)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
linuxKernel @ 6.18.55 (fixes >=4.6.0)—osv

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Data Freshness Timeline

(refreshed 8× in last 7d / 15× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

  1. 2026-11-03 16:49 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  2. 2026-11-02 16:46 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  3. 2026-11-01 16:36 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  4. 2026-10-31 18:25 UTCOSV refresh
  5. 2026-10-31 16:33 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  6. 2026-10-30 16:35 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  7. 2026-10-29 16:34 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  8. 2026-10-28 16:33 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  9. 2026-10-26 16:33 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  10. 2026-10-25 16:34 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  11. 2026-10-25 13:46 UTCEG score recompute
  12. 2026-10-24 16:34 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  13. 2026-10-23 13:25 UTCNVD update
  14. 2026-10-23 12:25 UTCEG score recompute
  15. 2026-10-23 12:24 UTCMITRE cvelistV5first tracked

Frequently asked(4)

What is CVE-2026-98929?
CVE-2026-98929 is a vulnerability whose severity is not yet rated; its CVE record was published on October 23, 2026. In the Linux kernel, the following vulnerability has been resolved: macsec: initialize SecY before registering the netdevice Creating a MACsec device with MAC offload over an LRO-capable lower device triggers a warning in rtmsg_ifinfo_build_skb() when IPv4 forwarding is enabled by default.…
When was the CVE record for CVE-2026-98929 published?
The CVE record for CVE-2026-98929 was published on October 23, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of October 23, 2026; the record at its source may have been updated since.
Is CVE-2026-98929 actively exploited?
CVE-2026-98929 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.2% probability of exploitation in the next 30 days (5th percentile of EPSS-scored CVEs).
How do I remediate CVE-2026-98929?
A fix for CVE-2026-98929 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-98929 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-98929

Explore →

Is Your Infrastructure Affected by CVE-2026-98929?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.