net: bridge: mrp: fix uninitialised bytes on the wire
Summary
| CVE | CVE-2026-74659 |
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| State | PUBLISHED |
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| Assigner | Linux |
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| Source Priority | CVE Program / NVD first with legacy fallback |
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| Published | 2026-08-22 16:16:39 UTC |
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| Updated | 2026-08-22 16:16:39 UTC |
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| Description | In the Linux kernel, the following vulnerability has been resolved:
net: bridge: mrp: fix uninitialised bytes on the wire
br_mrp_alloc_test_skb() builds MRP test frames on an skb from
dev_alloc_skb(), which does not clear the linear data area. On the MRA
ring-role branch the sub-option TLV header is appended with
sub_tlv = skb_put(skb, sizeof(*sub_tlv));
sub_tlv->type = BR_MRP_SUB_TLV_HEADER_TEST_AUTO_MGR;
so sub_tlv->length is never written, and the two trailing alignment bytes
are appended with a bare skb_put() that does not clear them either. The
neighbouring oui and sub_opt regions are explicitly zeroed, so three
uninitialised bytes are left in every MRA MRP_Test frame that goes out.
Put the sub-option TLV header and the alignment padding in a single
skb_put_zero(), which clears both. The AUTO_MGR sub-TLV carries no
payload, so the zeroed length field is already the value it should have. |
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Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|
| CNA |
Linux |
Linux |
affected f7458934b0791c39a001e4d902fc3bf697b439b5 014c062d23c63ec77ef2cf17a0d9363c7441cc94 git |
Not specified |
| CNA |
Linux |
Linux |
affected f7458934b0791c39a001e4d902fc3bf697b439b5 7ebc23ff03668042e0b0e4034bb1518d36198d9e git |
Not specified |
| CNA |
Linux |
Linux |
affected f7458934b0791c39a001e4d902fc3bf697b439b5 06d58b8d2f053ced82e01efaeb6e7c82891eed58 git |
Not specified |
| CNA |
Linux |
Linux |
affected f7458934b0791c39a001e4d902fc3bf697b439b5 a5e385eeb2d6dbbbdebfa050e67c34734ae12693 git |
Not specified |
| CNA |
Linux |
Linux |
affected f7458934b0791c39a001e4d902fc3bf697b439b5 5912cf1822fbe53ae275c147868740eb384a5d3e git |
Not specified |
| CNA |
Linux |
Linux |
affected f7458934b0791c39a001e4d902fc3bf697b439b5 e08665218040f8e312abe40f74543186f3c2c941 git |
Not specified |
| CNA |
Linux |
Linux |
affected f7458934b0791c39a001e4d902fc3bf697b439b5 63488dba65ef91373ef616575b32eb0eb21459f4 git |
Not specified |
| CNA |
Linux |
Linux |
affected 5.14 |
Not specified |
| CNA |
Linux |
Linux |
unaffected 5.14 semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 5.15.216 5.15.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.1.183 6.1.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.6.152 6.6.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.12.104 6.12.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.18.45 6.18.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 7.1.9 7.1.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 7.2 * original_commit_for_fix |
Not specified |
References
| Reference | Source | Link | Tags |
|---|
| git.kernel.org/stable/c/63488dba65ef91373ef616575b32eb0eb21459f4 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/5912cf1822fbe53ae275c147868740eb384a5d3e |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/014c062d23c63ec77ef2cf17a0d9363c7441cc94 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/06d58b8d2f053ced82e01efaeb6e7c82891eed58 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/e08665218040f8e312abe40f74543186f3c2c941 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/7ebc23ff03668042e0b0e4034bb1518d36198d9e |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/a5e385eeb2d6dbbbdebfa050e67c34734ae12693 |
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.