GHSA-v8w5-25mx-q5r4 · Severity: high — In the Linux kernel, the following vulnerability has been resolved: netfilter: nfnetlink_queue:...
In the Linux kernel, the following vulnerability has been resolved: netfilter: nfnetlink_queue: do shared-unconfirmed check before segmentation Ulrich reports a regression with nfqueue: If an application did not set the 'F_GSO' capability flag and a gso packet with an unconfirmed nf_conn entry is received all packets are now dropped instead of queued, because the check happens after skb_gso_segment(). In that case, we did have exclusive ownership of the skb and its associated conntrack entry. The elevated use count is due to skb_clone happening via skb_gso_segment(). Move the check so that its peformed vs. the aggregated packet. Then, annotate the individual segments except the first one so we can do a 2nd check at reinject time. For the normal case, where userspace does in-order reinjects, this avoids packet drops: first reinjected segment continues traversal and confirms entry, remaining segments observe the confirmed entry. While at it, simplify nf_ct_drop_unconfirmed(): We only care about unconfirmed entries with a refcnt > 1, there is no need to special-case dying entries. This only happens with UDP. With TCP, the only unconfirmed packet will be the TCP SYN, those aren't aggregated by GRO. Next patch adds a udpgro test case to cover this scenario.
Conclusion & alert: CVE-2026-45859 is rated Low Risk (36.1/100): CVSS High severity, with low exploitation likelihood (EPSS 0.06%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-06-02 | 0.02% | 0.06% | +0.04% |
| 2 | 2026-05-28 | — | 0.02% | — |
Full EPSS history (2 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 7.5 | 3.1 | HIGH |
|
3.9 | 3.6 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
GHSA-v8w5-25mx-q5r4 · Severity: high — In the Linux kernel, the following vulnerability has been resolved: netfilter: nfnetlink_queue:...
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
unimportant | CVE-2026-45859 unimportant priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 4, open 1. | https://security-tracker.debian.org/tracker/CVE-2026-45859 |
redhat
|
medium | — | https://access.redhat.com/security/cve/CVE-2026-45859 |
suse
|
— | — | https://www.suse.com/security/cve/CVE-2026-45859/ |
ubuntu
|
medium | CVE-2026-45859 medium priority: Ubuntu including 158 source packages (linux, linux-allwinner-5.19, …), 1422 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): DNE 1024, ignored 169, released 84, needed 71, not-affected 55, pending 18, needs-triage 1. | https://ubuntu.com/security/CVE-2026-45859 |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| No affected products in dataset. | |||