netfilter: xt_tcpmss: check remaining length before reading optlen
Summary
| CVE | CVE-2026-43190 |
|---|
| State | PUBLISHED |
|---|
| Assigner | Linux |
|---|
| Source Priority | CVE Program / NVD first with legacy fallback |
|---|
| Published | 2026-05-06 12:16:37 UTC |
|---|
| Updated | 2026-05-06 13:07:51 UTC |
|---|
| Description | In the Linux kernel, the following vulnerability has been resolved:
netfilter: xt_tcpmss: check remaining length before reading optlen
Quoting reporter:
In net/netfilter/xt_tcpmss.c (lines 53-68), the TCP option parser reads
op[i+1] directly without validating the remaining option length.
If the last byte of the option field is not EOL/NOP (0/1), the code attempts
to index op[i+1]. In the case where i + 1 == optlen, this causes an
out-of-bounds read, accessing memory past the optlen boundary
(either reading beyond the stack buffer _opt or the
following payload). |
|---|
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|
| CNA |
Linux |
Linux |
affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 f895191dc32c53eaf443b6443fe40945b2f92287 git |
Not specified |
| CNA |
Linux |
Linux |
affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 cd5beda7e0e32865e214f28034bb92c1cecff885 git |
Not specified |
| CNA |
Linux |
Linux |
affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 eaedc0bc18be46fe7f58170e967959a932c4f824 git |
Not specified |
| CNA |
Linux |
Linux |
affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 07a9b32eaae792ff7d0fcac14d8920c937c0a9c3 git |
Not specified |
| CNA |
Linux |
Linux |
affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 8b300f726640c48c3edfe9c453334dd801f4b74e git |
Not specified |
| CNA |
Linux |
Linux |
affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 5e13d0a37666955b6cfddc0f73cb40ed645b8a05 git |
Not specified |
| CNA |
Linux |
Linux |
affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 f6c412dcfd76b0516d51aa847d8f4c7b70381b09 git |
Not specified |
| CNA |
Linux |
Linux |
affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 735ee8582da3d239eb0c7a53adca61b79fb228b3 git |
Not specified |
| CNA |
Linux |
Linux |
unaffected 5.10.252 5.10.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 5.15.202 5.15.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.1.165 6.1.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.6.128 6.6.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.12.75 6.12.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.18.16 6.18.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.19.6 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/8b300f726640c48c3edfe9c453334dd801f4b74e |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/eaedc0bc18be46fe7f58170e967959a932c4f824 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/07a9b32eaae792ff7d0fcac14d8920c937c0a9c3 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/5e13d0a37666955b6cfddc0f73cb40ed645b8a05 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/f895191dc32c53eaf443b6443fe40945b2f92287 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/735ee8582da3d239eb0c7a53adca61b79fb228b3 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/cd5beda7e0e32865e214f28034bb92c1cecff885 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/f6c412dcfd76b0516d51aa847d8f4c7b70381b09 |
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.
