8.8

CVE-2026-63917: linux Use After Free

CVSS: 8.8v3.1HighAwaiting analysis
AliasesUBUNTU-CVE-2026-63917DEBIAN-CVE-2026-63917
Published 19-07-2026Last modified 19-10-2026
Open JSON

Vulnerability summary

CVE-2026-63917 is a high (CVSS 8.8) Use After Free vulnerability in linux. EPSS estimates a 0.17% chance of exploitation in the next 30 days, higher than 5.8% of scored vulnerabilities.

Overall risk
35/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.8/10
010
High · v3.1 (CVE.org)
EPSS score
0.17%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 169 · Related 157
OPENSUSE-SU-2026:21910-1RHSA-2026:67471RHSA-2026:68531RHSA-2026:68532RHSA-2026:68570RHSA-2026:74174

Showing 100 of 169. Use Open JSON for the complete list.

Timeline

  1. 19-07-2026
    PublishedVulnerability first disclosed.
  2. 19-10-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: ip6: vti: Use ip6_tnl.net in vti6_changelink(). ip netns add ns1 ip netns add ns2 ip -n ns1 link add vti6_test type vti6 remote ::1 local ::2 key 7 ip -n ns1 link set vti6_test netns ns2 ip -n ns2 link set vti6_test type vti6 remote ::3 local ::4 key 9 ip netns del ns2 ip netns del ns1 [ 132.495484] ------------[ cut here ]------------ [ 132.497609] kernel BUG at net/core/dev.c:12376! Commit 61220ab34948 ("vti6: Enable namespace changing") dropped NETIF_F_NETNS_LOCAL from vti6 devices. A vti6 tunnel can then move through IFLA_NET_NS_FD. After the move dev_net(dev) points at the new netns while t->net stays at the creation netns. vti6_changelink() and vti6_update() still use dev_net(dev) and dev_net(t->dev). They unlink from one per netns hash and relink into another. The creation netns is left with a stale entry. cleanup_net() of that netns later walks freed memory. Reachable from an unprivileged user namespace (unshare --user --map-root-user --net). Cross tenant scope on container hosts.

CVSS metrics

5 scores · 4 sources · 2 versions

EPSS trend

Probability

0.17%

Chance of exploitation in the next 30 days

Percentile

6%

Versus all other CVEs

30-day change

0.00 pp

From 0.17% on 20-09-2026

20-09-202620-10-2026
EPSS score
0.17%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Ubuntu167 products
  • linuxAll versions (No fix recorded) | < 5.15.0-198.208 | < 6.8.0-146.146 | < 7.0.0-28.28
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded) | < 5.15.0-1117.124 | < 6.8.0-1066.69 | < 7.0.0-1009.9
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Debian1 product
  • linux< 6.1.176-1 | < 6.12.94-1 | < 7.0.12-1
Linux1 product
  • linux≥ 61220ab349485d911083d0b7990ccd3db6c63297, < 0cdce7618464f7fb06f461e8f4ad575cb1d570f4 | ≥ 61220ab349485d911083d0b7990ccd3db6c63297, < f5c68875e25f331e497ddfbe81e2d8163a87f136 | ≥ 61220ab349485d911083d0b7990ccd3db6c63297, < d9c5eecdb3c740e65038651db7c686b10d76d1bc | ≥ 61220ab349485d911083d0b7990ccd3db6c63297, < f1e89a943ee574d0f2f16246eb3f2d7330fdeb03 | ≥ 61220ab349485d911083d0b7990ccd3db6c63297, < 225b467e3b631f38be22e4b38062a1fed02fdd21 | ≥ 61220ab349485d911083d0b7990ccd3db6c63297, < fc32be9ac2788524c6b24efd681cce7a6e731a92 | ≥ 61220ab349485d911083d0b7990ccd3db6c63297, < ee1778ba0f5cb53be771f97017d01eb356c797bf | ≥ 61220ab349485d911083d0b7990ccd3db6c63297, < 11b326fb0a374f4654f9be22d0f0f7abd9f7d3fe | 3.15

3 vendors · 169 products

References

32 links
Show all 32 references