CVE-2026-99057 json
xen/netfront: don't leak the skb when xennet_fill_frags() fails
published 19d ago modified 12d ago also EUVD-2026-108852
- 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 8%
- public exploits
- 0
- none known
Summary
In the Linux kernel, the following vulnerability has been resolved:
xen/netfront: don't leak the skb when xennet_fill_frags() fails
When a response chain has more slots than fit in the skb's frags, xennet_fill_frags() returns an error and xennet_poll() jumps to its error path. That path moves what's left on tmpq to errq to be freed, but the skb being filled was already dequeued from tmpq, so it's never freed. Each chain that overflows leaks the skb and the pages attached to it as frags, and the backend decides how many slots it sends.
Put the skb back on tmpq before taking the error path, like the xennet_set_skb_gso() failure just above it does.
Patch / fix
- Linux Linux 4.5, 4.10, 4.15, 4.19, 7.3
- linux Debian 13 6.12.113-1
- linux Debian 14 7.2.11-1
debian advisories DEBIAN-CVE-2026-99057
- 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-2026-99057
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
- kernel Azure Linux 3.0 6.6.161.1-1
azure linux advisories AZL-110942
Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT
- git.kernel.org/stable/c/6e6bd1051daabc327233c3ca3d00613fc6783c8e commit
- git.kernel.org/stable/c/0cf0a25a639c535146c5eb4480d256995721aed6 commit
- git.kernel.org/stable/c/53a131eb2a998c77e2851401b32b712d6c6e8487 commit
- git.kernel.org/stable/c/5051df031144753d3e18862514969146b601d089 commit
- git.kernel.org/stable/c/99011a11c97340ef7290df7dc199305c73fab2f2 commit
- git.kernel.org/stable/c/086944c1c2cbb683543bc3ff08637847b03c8009 commit
- git.kernel.org/stable/c/84e3ea6502b5f14ce8d499d0b6e0e38386274cf0 commit
- git.kernel.org/stable/c/93ccaf1c26e2133396173b76a071e59024daa622 commit
Is CVE-2026-99057 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
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-2026-99057 updated cvss 2.3
kernel: xen/netfront: don't leak the skb when xennet_fill_frags() fails
-
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, +83 more Red Hat Enterprise Linux 10 kernel Red Hat OpenShift Container Platform 4 openshift/ose-rhel-coreos-9 Red Hat OpenShift Container Platform 5 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 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
0.19% chance of exploitation in the next 30 days, higher than 8% of all scored CVEs (FIRST EPSS, 2026-11-11).
Affected products
- Linux Linux
Classification
- Technology feeds
References
- git.kernel.org /stable/c/6e6bd1051daabc327233c3ca3d00613fc6783c8e
- git.kernel.org /stable/c/0cf0a25a639c535146c5eb4480d256995721aed6
- git.kernel.org /stable/c/53a131eb2a998c77e2851401b32b712d6c6e8487
- git.kernel.org /stable/c/5051df031144753d3e18862514969146b601d089
- git.kernel.org /stable/c/99011a11c97340ef7290df7dc199305c73fab2f2
- git.kernel.org /stable/c/086944c1c2cbb683543bc3ff08637847b03c8009
- git.kernel.org /stable/c/84e3ea6502b5f14ce8d499d0b6e0e38386274cf0
- git.kernel.org /stable/c/93ccaf1c26e2133396173b76a071e59024daa622
Sources
- CVE List CVE-2026-99057
- NVD CVE-2026-99057
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