Linux KernelOperating system · Linux
CVE-2026-52974
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedIn the Linux kernel, the following vulnerability has been resolved: net: tls: fix strparser anchor skb leak on offload RX setup failure When tls_set_device_offload_rx() fails at tls_dev_add(), the error path calls tls_sw_free_resources_rx() to clean up the SW context that was initialized by tls_set_sw_offload(). This function calls tls_sw_release_resources_rx() (which stops the strparser via tls_strp_stop()) and tls_sw_free_ctx_rx() (which kfrees the context), but never frees the anchor skb that was allocated by alloc_skb(0) in tls_strp_init(). Note that tls_sw_free_resources_rx() is exclusively used for this "failed to start offload" code path, there's no other caller. The leak did not exist before commit 84c61fe1a75b ("tls: rx: do not use the standard strparser"), because the standard strparser doesn't try to pre-allocate an skb. The normal close path in tls_sk_proto_close() handles cleanup by calling tls_sw_strparser_done() (which calls tls_strp_done()) after dropping the socket lock, because tls_strp_done() does cancel_work_sync() and the strparser work handler takes the socket lock.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceMemory leak in Linux kernel TLS subsystem where the anchor skb (socket buffer) allocated during tls_strp_init() is not freed when tls_set_device_offload_rx() fails at tls_dev_add(). The error cleanup path calls tls_sw_free_resources_rx() which frees the context but leaks the skb allocated by alloc_skb(0).
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data
Linux KernelOperating system
>= 6.0, < 6.1.175>= 6.2, < 6.6.141>= 6.7, < 6.12.91>= 6.13, < 6.18.33>= 6.19, < 7.0.10= 7.1CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Check kernel versionRun `uname -r` or `cat /proc/version` to determine the running kernel versionAffected if The kernel version falls within any of these ranges: 6.0 to 6.1.174, 6.2 to 6.6.140, 6.7 to 6.12.90, 6.13 to 6.18.32, 6.19 to 7.0.9, or exactly 7.1
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Verify TLS device offload is supportedCheck if the kernel was compiled with TLS device offload support: `grep -i tls /boot/config-$(uname -r)` or `zcat /proc/config.gz 2>/dev/null | grep -i TLS`Affected if CONFIG_TLS_DEVICE or CONFIG_TLS is set to y or m, indicating TLS offload capability is compiled in
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Check for TLS offload capable network interfacesRun `ethtool -k <interface> | grep tls` on suspected interfaces (e.g., eth0, ens160) to see if TLS hardware offload is advertised as supportedAffected if The interface shows tls-hw-tx-offload or tls-hw-rx-offload as supported in ethtool output
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Inspect active TLS offload sessionsCheck /proc/net/tls for active TLS connections using offload: `cat /proc/net/tls` and look for 'hw' in the connection infoAffected if There are active TLS connections using hardware offload (indicated by 'hw' flag or offload statistics in the output)
The system is affected if the kernel version is within the vulnerable ranges AND TLS device offload is enabled/active, specifically when a TLS RX offload setup attempt fails via tls_set_device_offload_rx().
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped6.1.1756.6.1416.12.91
This is a kernel code bug requiring a patch to free the anchor skb in the error path within tls_sw_free_resources_rx(). No configuration workaround exists; systems using TLS device offload RX should ensure kernel is updated once patch is available.
6.1.175, 6.6.141, 6.12.91, or 6.18.33 (depending on which branch you are on)
- Upgrade the Linux kernel to version 6.1.175 or later for the 6.1.y branch
- Alternatively, upgrade to version 6.6.141 or later for the 6.6.y branch
- Alternatively, upgrade to version 6.12.91 or later for the 6.12.y branch
- Alternatively, upgrade to version 6.18.33 or later for the 6.13+ branch
- After upgrade, verify the fix is present by checking the kernel version with: uname -r
Generated from the published advisory — verify against the referenced sources before acting.
Fix this in Linux Kernel
Scoped from the published advisory
- Consultation1.0 h
- Implementation2.0 h
- Testing4.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,432.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-52974 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-52974 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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