net/tcp-md5: Fix MAC comparison to be constant-time
Published May 8, 2026
9.4
CRITICALCVSS 3.1
EPSS 0.65%
Description
To prevent timing attacks, MACs need to be compared in constant time. Use the appropriate helper function for this.
Affected products
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- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version
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- Version 2.6.20StatusaffectedConstraints-
- Version 0StatusunaffectedConstraints<2.6.20
- Version 5.10.253StatusunaffectedConstraints<=5.10.*
- Version 5.15.210StatusunaffectedConstraints<=5.15.*
- Version 6.1.167StatusunaffectedConstraints<=6.1.*
- Version 6.12.78StatusunaffectedConstraints<=6.12.*
- Version 6.18.19StatusunaffectedConstraints<=6.18.*
- Version 6.19.9StatusunaffectedConstraints<=6.19.*
- Version 6.6.130StatusunaffectedConstraints<=6.6.*
- Version 7.0StatusunaffectedConstraints<=*
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | |||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Linux | Linux | unaffected |
| |||||||||||||||||||||||||||||||||
| Linux | Linux | affected |
|
- ≥ 2.6.20 · < 5.10.253
- ≥ 5.11 · < 6.1.167
- ≥ 6.2 · < 6.6.130
- ≥ 6.7 · < 6.12.78
- ≥ 6.13 · < 6.18.19
- ≥ 6.19 · < 6.19.9
- 7.0
- 7.0
No data.
Red Hat Enterprise Linux 10
kernel
Fix deferred
Red Hat Enterprise Linux 6
kernel
Out of support scope
Red Hat Enterprise Linux 7
kernel
Fix deferred
Red Hat Enterprise Linux 7
kernel-rt
Fix deferred
Red Hat Enterprise Linux 8
kernel
Fix deferred
Red Hat Enterprise Linux 8
kernel-rt
Out of support scope
Red Hat Enterprise Linux 9
kernel
Fix deferred
Red Hat Enterprise Linux 9
kernel-rt
Fix deferred
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 10 | kernel | Fix deferred | n/a |
| Red Hat Enterprise Linux 6 | kernel | Out of support scope | n/a |
| Red Hat Enterprise Linux 7 | kernel | Fix deferred | n/a |
| Red Hat Enterprise Linux 7 | kernel-rt | Fix deferred | n/a |
| Red Hat Enterprise Linux 8 | kernel | Fix deferred | n/a |
| Red Hat Enterprise Linux 8 | kernel-rt | Out of support scope | n/a |
| Red Hat Enterprise Linux 9 | kernel | Fix deferred | n/a |
| Red Hat Enterprise Linux 9 | kernel-rt | Fix deferred | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
Red Hat acknowledges the upstream Linux kernel correction for «net/tcp-md5» as described in COMMENT_ZERO. Fixes are delivered through standard kernel errata for supported products. Operational exposure depends on whether this subsystem or driver is active in your configuration.
References (14)
- https://access.redhat.com/security/cve/CVE-2026-43383 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2468242 Issue Tracking
- https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-28689 Advisory
- https://git.kernel.org/stable/c/02669e2a4d207068edce7e8b5fafd85822018ce6 Patch
- https://git.kernel.org/stable/c/345a9530756528d7ca407663d659c3c40e75c3dd Patch
- https://git.kernel.org/stable/c/46d0d6f50dab706637f4c18a470aac20a21900d3 Patch
- https://git.kernel.org/stable/c/5d305a95130a8d08b9545e47f1e18d29d59866cb Patch
- https://git.kernel.org/stable/c/821c8751fdeecdeecabeb11704dd33439c9e4bbc Patch
- https://git.kernel.org/stable/c/ae3831b44f477de048287493e184fc3ff913b624 Patch
- https://git.kernel.org/stable/c/b502e97e29d791ff7a8051f29a414535739be218 Patch
- https://git.kernel.org/stable/c/ff44ec94d4fc8348600a69de0a8fa1102c23bce8
- https://lore.kernel.org/linux-cve-announce/2026050833-CVE-2026-43383-0333@gregkh/T
- https://nvd.nist.gov/vuln/detail/CVE-2026-43383
- https://www.cve.org/CVERecord?id=CVE-2026-43383
Change history (0)
No recorded changes yet.