Unspecified impact via unsafe RCU list updates
Published Sep 25, 2026 · Updated Sep 25, 2026
Race condition in Linux kernel IPv6 multicast handling allows attackers to cause unspecified impact via concurrent list access. Functions in net/ipv6/mcast.c directly assign RCU-protected np->ipv6_mc_list, idev->mc_list, and idev->mc_tomb pointers while readers traverse them without locks, rather than publishing updates through rcu_assign_pointer(). The public record does not identify a reliable attacker-controlled trigger or bound the resulting effect beyond unsafe concurrent multicast-list observation.
Summary
What happened
Race condition in Linux kernel IPv6 multicast handling allows attackers to cause unspecified impact via concurrent list access. Functions in net/ipv6/mcast.c directly assign RCU-protected np->ipv6_mc_list, idev->mc_list, and idev->mc_tomb pointers while readers traverse them without locks, rather than publishing updates through rcu_assign_pointer(). The public record does not identify a reliable attacker-controlled trigger or bound the resulting effect beyond unsafe concurrent multicast-list observation.
The record
- CVE
- CVE-2026-98099
- Published
- Sep 25, 2026
- Updated
- Sep 25, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- Unavailable
- Attack vector
- Unavailable
- Privileges
- Unavailable
Timeline
How it unfolded
- Sep 25, 2026CVE publishedPublication date reported by the CVE source.
- Sep 25, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=2.6.38
- Affected versionversion=456b61bca8ee324ab6c18b065e632c9a8c88aa39 <0c8f56c583c3250408367880c98e4d6fbc929315
- Affected versionversion=456b61bca8ee324ab6c18b065e632c9a8c88aa39 <2e46b0c9fcf7e10b64ce1630b925f47918d1f7f6
What conditions does exploitation require?
What is affected?
Published CVSS scores
No CVSS assessment is available in this record.
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Activity data is delayed. The latest report is Sep 28, 2026.
Weakness, pattern, technique
No sourced classifications are available.
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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