CVE-2026-99073 json
ipv4: stop exception dump when nexthop group shrinks
published 19d ago modified 19d ago also EUVD-2026-108739
- cvss
- —
- not scored
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 4%
- public exploits
- 0
- none known
Summary
In the Linux kernel, the following vulnerability has been resolved:
ipv4: stop exception dump when nexthop group shrinks
Commit 4ce5dc9316de ("inet: switch inet_dump_fib() to RCU protection") allowed IPv4 FIB dumps to run concurrently with nexthop replacement.
fib_dump_info_fnhe() uses fib_info_num_path() as the loop bound, then fib_info_nhc() independently reloads nh->nh_grp. If RTM_NEWNEXTHOP replaces a group with fewer paths between those loads, fib_info_nhc() returns NULL and the dump dereferences it through nhc_flags.
Stop the walk when the indexed path is absent. Nexthop groups are dense, so the current snapshot has no later path.
Patch / fix
- Linux Linux 7.3
- linux Debian 13 6.12.113-1
- linux Debian 14 7.2.11-1
debian advisories DEBIAN-CVE-2026-99073
- linux Ubuntu 26.10 7.3.0-10.10
- linux-aws Ubuntu 26.10 7.3.0-1004.4
- linux-gcp Ubuntu 26.10 7.3.0-1004.4
- linux-raspi Ubuntu 26.10 7.3.0-1004.4
- linux-riscv Ubuntu 26.10 7.3.0-10.10.1
- linux-oracle Ubuntu 26.10 7.3.0-1004.4
- linux-realtime Ubuntu 26.10 7.3.0-10.10.1
ubuntu advisories UBUNTU-CVE-2026-99073
Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0
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Check with FencerVendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
red hat product security vex CVE-2026-99073 updated cvss 5.5
kernel: ipv4: stop exception dump when nexthop group shrinks
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Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 moreaffected: no fix planned “Out of support scope”
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Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +82 more Red Hat Enterprise Linux 10 kernel Red Hat OpenShift Container Platform 4 openshift/ose-rhel-coreos-9affected: no fix available “Fix deferred”
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Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 kernel-rt, kernel-rt-selftests-internal Red Hat OpenShift Container Platform 4 openshift/ose-rhel-coreos-8not affected: vulnerable code not present
Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf
Exploit prediction
0.16% chance of exploitation in the next 30 days, higher than 4% of all scored CVEs (FIRST EPSS, 2026-11-11).
Affected products
- Linux Linux
Classification
- Technology feeds
References
Sources
- CVE List CVE-2026-99073
- NVD CVE-2026-99073
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