CVE-2026-53013macvlan: fix macvlan_get_size() not reserving space for IFLA_MACVLAN_BC_CUTOFF
- 5.5MediumCVSS base score
- 0.12%Exploitation in 30 daysEPSS · top 98% 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: macvlan: fix macvlan_get_size() not reserving space for IFLA_MACVLAN_BC_CUTOFF macvlan_get_size() does not account for IFLA_MACVLAN_BC_CUTOFF, but macvlan_fill_info() conditionally includes it when port->bc_cutoff != 1. This causes nla_put_s32() to fail with -EMSGSIZE when the netlink skb runs out of space, triggering a WARN_ON in rtnetlink and preventing the interface from being dumped. The bug can be reproduced with: ip link add macvlan0 link eth0 type macvlan mode bridge ip link set macvlan0 type macvlan bc_cutoff 0 ip -d link show macvlan0 # fails with -EMSGSIZE The bc_cutoff feature was added in commit 954d1fa1ac93 ("macvlan: Add netlink attribute for broadcast cutoff"), which added the nla_put_s32() call in macvlan_fill_info() but missed adding the corresponding nla_total_size(4) in macvlan_get_size(). A follow-up commit 55cef78c244d ("macvlan: add forgotten nla_policy for IFLA_MACVLAN_BC_CUTOFF") fixed the missing nla_policy entry but still did not fix the size calculation.
Timeline
ID reserved
By Linux
- 15 days later
· 15 days later
Published
- 5 months later
· 5 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 |
|---|---|---|---|
| NVDNVD · Analyzed | 3.1 | Medium5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.12% · top 98% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.5.
Affected products
- affected 954d1fa1ac93aa8a66f7d9a9ba545cf7f020d348 – < 4979252758387b338ca968ba7e0515b0ae2257e3
- affected 954d1fa1ac93aa8a66f7d9a9ba545cf7f020d348 – < 77ecfa4e27f282d224215895ddfbeb916fc75e24
- affected 954d1fa1ac93aa8a66f7d9a9ba545cf7f020d348 – < b6b7154e9f5d75b608ceb2d05b376de8c638c40e
- affected 954d1fa1ac93aa8a66f7d9a9ba545cf7f020d348 – < 1c004f14ccdc11585625c168bb9a7c5e1b8afb0c
- affected 954d1fa1ac93aa8a66f7d9a9ba545cf7f020d348 – < fa92a77b0ed4d5f11a71665a232ac5a54a4b055d
- affected 6.4
- unaffected < 6.4
- unaffected 6.6.141 – ≤ 6.6.*
- unaffected 6.12.91 – ≤ 6.12.*
- unaffected 6.18.33 – ≤ 6.18.*
- unaffected 7.0.10 – ≤ 7.0.*
- unaffected 7.1 – ≤ *
References
References5
- https://git.kernel.org/stable/c/4979252758387b338ca968ba7e0515b0ae2257e3 (opens in a new tab)
- https://git.kernel.org/stable/c/77ecfa4e27f282d224215895ddfbeb916fc75e24 (opens in a new tab)
- https://git.kernel.org/stable/c/b6b7154e9f5d75b608ceb2d05b376de8c638c40e (opens in a new tab)
- https://git.kernel.org/stable/c/1c004f14ccdc11585625c168bb9a7c5e1b8afb0c (opens in a new tab)
- https://git.kernel.org/stable/c/fa92a77b0ed4d5f11a71665a232ac5a54a4b055d (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-2026-38881 (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-2026-53013)Record last updated .