CVE-2026-31469virtio_net: Fix UAF on dst_ops when IFF_XMIT_DST_RELEASE is cleared and napi_tx is false
- 7.8HighCVSS base score
- 0.14%Exploitation in 30 daysEPSS · top 97% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In the Linux kernel, the following vulnerability has been resolved: virtio_net: Fix UAF on dst_ops when IFF_XMIT_DST_RELEASE is cleared and napi_tx is false A UAF issue occurs when the virtio_net driver is configured with napi_tx=N and the device's IFF_XMIT_DST_RELEASE flag is cleared (e.g., during the configuration of tc route filter rules). When IFF_XMIT_DST_RELEASE is removed from the net_device, the network stack expects the driver to hold the reference to skb->dst until the packet is fully transmitted and freed. In virtio_net with napi_tx=N, skbs may remain in the virtio transmit ring for an extended period. If the network namespace is destroyed while these skbs are still pending, the corresponding dst_ops structure has freed. When a subsequent packet is transmitted, free_old_xmit() is triggered to clean up old skbs. It then calls dst_release() on the skb associated with the stale dst_entry. Since the dst_ops (referenced by the dst_entry) has already been freed, a UAF kernel paging request occurs. fix it by adds skb_dst_drop(skb) in start_xmit to explicitly release the dst reference before the skb is queued in virtio_net. Call Trace: Unable to handle kernel paging request at virtual address ffff80007e150000 CPU: 2 UID: 0 PID: 6236 Comm: ping Kdump: loaded Not tainted 7.0.0-rc1+ #6 PREEMPT ... percpu_counter_add_batch+0x3c/0x158 lib/percpu_counter.c:98 (P) dst_release+0xe0/0x110 net/core/dst.c:177 skb_release_head_state+0xe8/0x108 net/core/skbuff.c:1177 sk_skb_reason_drop+0x54/0x2d8 net/core/skbuff.c:1255 dev_kfree_skb_any_reason+0x64/0x78 net/core/dev.c:3469 napi_consume_skb+0x1c4/0x3a0 net/core/skbuff.c:1527 __free_old_xmit+0x164/0x230 drivers/net/virtio_net.c:611 [virtio_net] free_old_xmit drivers/net/virtio_net.c:1081 [virtio_net] start_xmit+0x7c/0x530 drivers/net/virtio_net.c:3329 [virtio_net] ... Reproduction Steps: NETDEV="enp3s0" config_qdisc_route_filter() { tc qdisc del dev $NETDEV root tc qdisc add dev $NETDEV root handle 1: prio tc filter add dev $NETDEV parent 1:0 \ protocol ip prio 100 route to 100 flowid 1:1 ip route add 192.168.1.100/32 dev $NETDEV realm 100 } test_ns() { ip netns add testns ip link set $NETDEV netns testns ip netns exec testns ifconfig $NETDEV 10.0.32.46/24 ip netns exec testns ping -c 1 10.0.32.1 ip netns del testns } config_qdisc_route_filter test_ns sleep 2 test_ns
Timeline
ID reserved
By Linux
- 44 days later
· 44 days later
Published
- 7 months later
· 7 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.14% · top 97% of all CVEs (15 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.8.
Affected products
- affected f2fc6a54585a1be6669613a31fbaba2ecbadcd36 – < be0e63f3b97bbaf453c542e8a15ba2a536e2ac01
- affected f2fc6a54585a1be6669613a31fbaba2ecbadcd36 – < c1ec36cb3768574b916f20d2d7415fd14fa1bf12
- affected f2fc6a54585a1be6669613a31fbaba2ecbadcd36 – < 8a4790850e710fd6771e4d2112168ed1dd6c0e54
- affected f2fc6a54585a1be6669613a31fbaba2ecbadcd36 – < fedd2e1630cac920844997227ccbe7b26a76375a
- affected f2fc6a54585a1be6669613a31fbaba2ecbadcd36 – < f04733c4dc40c43899c3d1c97afbae5831a3770f
- affected f2fc6a54585a1be6669613a31fbaba2ecbadcd36 – < 9a18629f2525781f0f3dda7be72b204e4cf77d08
- affected f2fc6a54585a1be6669613a31fbaba2ecbadcd36 – < 63d45077b97bb0e0fe0c75931acbbca7a47af141
- affected f2fc6a54585a1be6669613a31fbaba2ecbadcd36 – < ba8bda9a0896746053aa97ac6c3e08168729172c
- affected 2.6.26
- unaffected < 2.6.26
- unaffected 5.10.253 – ≤ 5.10.*
- unaffected 5.15.203 – ≤ 5.15.*
- unaffected 6.1.168 – ≤ 6.1.*
- unaffected 6.6.131 – ≤ 6.6.*
- unaffected 6.12.80 – ≤ 6.12.*
- unaffected 6.18.21 – ≤ 6.18.*
- unaffected 6.19.11 – ≤ 6.19.*
- unaffected 7.0 – ≤ *
References
References11
- https://git.kernel.org/stable/c/be0e63f3b97bbaf453c542e8a15ba2a536e2ac01 (opens in a new tab)
- https://git.kernel.org/stable/c/c1ec36cb3768574b916f20d2d7415fd14fa1bf12 (opens in a new tab)
- https://git.kernel.org/stable/c/8a4790850e710fd6771e4d2112168ed1dd6c0e54 (opens in a new tab)
- https://git.kernel.org/stable/c/fedd2e1630cac920844997227ccbe7b26a76375a (opens in a new tab)
- https://git.kernel.org/stable/c/f04733c4dc40c43899c3d1c97afbae5831a3770f (opens in a new tab)
- https://git.kernel.org/stable/c/9a18629f2525781f0f3dda7be72b204e4cf77d08 (opens in a new tab)
- https://git.kernel.org/stable/c/63d45077b97bb0e0fe0c75931acbbca7a47af141 (opens in a new tab)
- https://git.kernel.org/stable/c/ba8bda9a0896746053aa97ac6c3e08168729172c (opens in a new tab)
- https://cert-portal.siemens.com/productcert/html/ssa-082556.html (opens in a new tab)
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html (opens in a new tab)
- https://cert-portal.siemens.com/productcert/html/ssa-457936.html (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-24817 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-31469)Record last updated .