netfilter: nfnetlink_log: fix uninitialized padding leak in NFULA_PAYLOAD
Summary
| CVE | CVE-2026-31428 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-04-13 14:16:12 UTC |
| Updated | 2026-04-18 09:16:32 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: netfilter: nfnetlink_log: fix uninitialized padding leak in NFULA_PAYLOAD __build_packet_message() manually constructs the NFULA_PAYLOAD netlink attribute using skb_put() and skb_copy_bits(), bypassing the standard nla_reserve()/nla_put() helpers. While nla_total_size(data_len) bytes are allocated (including NLA alignment padding), only data_len bytes of actual packet data are copied. The trailing nla_padlen(data_len) bytes (1-3 when data_len is not 4-byte aligned) are never initialized, leaking stale heap contents to userspace via the NFLOG netlink socket. Replace the manual attribute construction with nla_reserve(), which handles the tailroom check, header setup, and padding zeroing via __nla_reserve(). The subsequent skb_copy_bits() fills in the payload data on top of the properly initialized attribute. |
Risk And Classification
EPSS: 0.000240000 probability, percentile 0.066100000 (date 2026-04-18)
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected df6fb868d6118686805c2fa566e213a8f31c8e4f 7f3e5d72455936f42709116fabeca3bb216cda62 git | Not specified |
| CNA | Linux | Linux | affected df6fb868d6118686805c2fa566e213a8f31c8e4f 21d8efda029948d3666b0db5afcc0d36c0984aae git | Not specified |
| CNA | Linux | Linux | affected df6fb868d6118686805c2fa566e213a8f31c8e4f fc961dd7272b5e4a462999635e44a4770d7f2482 git | Not specified |
| CNA | Linux | Linux | affected df6fb868d6118686805c2fa566e213a8f31c8e4f a8365d1064ded323797c5e28e91070c52f44b76c git | Not specified |
| CNA | Linux | Linux | affected df6fb868d6118686805c2fa566e213a8f31c8e4f a2f6ff3444b663d6cfa63eadd61327a18592885a git | Not specified |
| CNA | Linux | Linux | affected df6fb868d6118686805c2fa566e213a8f31c8e4f c9f6c51d36482805ac3ffadb9663fe775a13e926 git | Not specified |
| CNA | Linux | Linux | affected df6fb868d6118686805c2fa566e213a8f31c8e4f 7eff72968161fb8ddb26113344de3b92fb7d7ef5 git | Not specified |
| CNA | Linux | Linux | affected df6fb868d6118686805c2fa566e213a8f31c8e4f 52025ebaa29f4eb4ed8bf92ce83a68f24ab7fdf7 git | Not specified |
| CNA | Linux | Linux | affected 2.6.24 | Not specified |
| CNA | Linux | Linux | unaffected 2.6.24 semver | Not specified |
| CNA | Linux | Linux | unaffected 5.10.253 5.10.* semver | Not specified |
| CNA | Linux | Linux | unaffected 5.15.203 5.15.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.1.168 6.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.131 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.80 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.21 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.19.11 6.19.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.0 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/a2f6ff3444b663d6cfa63eadd61327a18592885a | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/a8365d1064ded323797c5e28e91070c52f44b76c | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/21d8efda029948d3666b0db5afcc0d36c0984aae | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/7f3e5d72455936f42709116fabeca3bb216cda62 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/c9f6c51d36482805ac3ffadb9663fe775a13e926 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/fc961dd7272b5e4a462999635e44a4770d7f2482 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/7eff72968161fb8ddb26113344de3b92fb7d7ef5 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/52025ebaa29f4eb4ed8bf92ce83a68f24ab7fdf7 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.