medium CVSS 6.2

CVE-2024-50251·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_payload: sanitize offset and length before calling skb_checksum() If access to offset + length is larger than the skbuff length, then skb_checksum() triggers BUG_ON(). skb_checksum() internally subtracts the length parameter while iterating over skbuff, BUG_ON(len) at the end of it checks that the expected length to be included in the checksum calculation is fully consumed.

Severity
medium
Software
Kernel
Fixed in
6.11.7
Published
2024-11-09

Affected versions

From: 6.7

Until: 6.11.7

Fixed in: 6.11.7

How to fix this CVE

Update your Linux kernel to version 6.11.7 or later to patch the netfilter payload validation flaw. This vulnerability allows a denial-of-service condition when malformed netfilter rules attempt to access memory beyond the packet buffer boundaries. Prioritize this update for systems running kernel versions 6.7 through 6.11.6 that use netfilter for packet filtering or NAT operations.

sudo dnf update kernel kernel-devel

Defensia detects this vulnerability

How to check if you are affected

  1. Check your kernel version: uname -r — compare against 6.11.7; if lower than 6.11.7 and within 6.7–6.11.6 range, you are vulnerable
  2. Verify netfilter is loaded: lsmod | grep nf_ — if any netfilter modules appear, the vulnerable component is active
  3. Search kernel logs for BUG_ON crashes: sudo dmesg | grep -i 'bug\|panic' | grep -i nft — exploitation may trigger kernel panics or oops messages
  4. Confirm the patch after upgrade: uname -r — should report kernel version 6.11.7 or higher

FAQ

What is CVE-2024-50251?

This is a kernel vulnerability in the netfilter subsystem where insufficient validation of packet offset and length parameters can trigger a kernel panic when skb_checksum() processes out-of-bounds memory access. The flaw affects the nft_payload module used in firewall and NAT configurations.

Is CVE-2024-50251 being actively exploited?

No, there is no evidence of active exploitation in the wild. The vulnerability requires local access or the ability to send specially crafted packets through netfilter rules, making it a lower risk for most internet-facing systems.

What versions of Kernel are affected by CVE-2024-50251?

Linux kernel versions 6.7 through 6.11.6 are vulnerable. Kernel 6.11.7 and later releases include the patch.

How do I check if my server is vulnerable to CVE-2024-50251?

Run 'uname -r' to display your kernel version. If it is 6.7.x, 6.8.x, 6.9.x, 6.10.x, or 6.11.0–6.11.6, your system is vulnerable. Cross-reference with 'lsmod | grep nft' to confirm netfilter modules are in use.

Does Defensia detect CVE-2024-50251?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Kernel is installed on a monitored server, CVE-2024-50251 will appear in your dashboard with remediation steps.

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CVE-2026-64439CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: crypto: krb5 - filter out async aead implementations at alloc krb5_aead_encrypt(), krb5_aead_decrypt() in rfc3961_simplified.c and rfc8009_encrypt(), rfc8009_decrypt() in rfc8009_aes2.c set a NULL completion callback and treat any negative return from crypto_aead_{encrypt,decrypt}() as terminal, falling through to kfree_sensitive(buffer). When the encrypt_name resolves to an async AEAD instance the request returns -EINPROGRESS, the buffer is freed while the backend's worker still holds a pointer, and the worker dereferences the freed slab on completion. KASAN report under UML+SLUB with a synthetic async aead backend bound to krb5->encrypt_name: BUG: KASAN: slab-use-after-free in t5_stub_complete+0x7d/0xc7 The helpers were written synchronously, so filter the async instances out at allocation time instead of plumbing crypto_wait_req() through every call site. Reachable via net/rxrpc/rxgk.c, fs/afs/cm_security.c and net/ceph/crypto.c on systems with an async AEAD provider bound to the krb5 enctype name.
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References

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