CVE-2026-53218
In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_exthdr: fix…
- Risk score
- 48/100
- CVSS
- 5.5 v3.1
- Exploit chance (30 days)
- 0.1%
- Published
- 25 Jun 2026
Open in the live forecast Today's forecast
What to know
- What it is
- In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_exthdr: fix register tracking for F_PRESENT flag nft_exthdr_init() passes user-controlled priv->len to nft_parse_register_store(), which marks that many bytes in the register bitmap as initialized. However, when NFT_EXTHDR_F_PRESENT is …
- Affected
- Linux kernel
- Fix
- Apply the vendor's security update; see the linked advisory.
- Exploitation
- No known exploitation
Story map
At a glance
Linux kernel: Amber, patch this week. In the Linux kernel, the following vulnerability has been resolved: ipv6: sr: restore network header before routing and forwarding ipv6_srh_rcv() runs with skb->data at the Segment Routing Header (SRH) while skb_network_header() points at the IPv6 header. When segments_left > 0, ipv6_srh_rcv() previously restored the …
The flaws
- CVE-2026-53218: In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_exthdr: fix… (CVSS 5.5 · EPSS 0%)
- CVE-2026-98096: Out-of-bounds write (CVSS 7.4 · EPSS 1%)
- CVE-2026-98115: Race condition (CVSS 8.8 · EPSS 0%)
- CVE-2026-98117: Use-after-free (CVSS 7.8 · EPSS 0%)
The fix
Fix: Apply the vendor's security update; see the linked advisory.
Who is exposed: Linux kernel
Where it stands
- No known exploitation
How it unfolded
- 6 Nov, Ubuntu security notices (official): USN-9002-1: Linux kernel (NVIDIA Tegra) vulnerabilities
Connects to
- Same weakness: CWE-908 (CWE-908). 68 other warnings in 30 days
- Same product: Earlier Linux kernel warnings. 176 in the last 90 days
Why it is Yellow
- CVSS 5.5 medium
- On your watchlist: linux kernel
- Named in a government or vendor bulletin
Government and vendor bulletins
References
- https://ubuntu.com/security/notices/USN-9002-1
- https://git.kernel.org/stable/c/19748967d59c31d24d21d40b728570788310b237
- https://git.kernel.org/stable/c/46fc15a044e9938e7ea77786fb37edd2cd74f031
- https://git.kernel.org/stable/c/67b27434c43b68a97becda98c9f0c8cf6cba2134
- https://git.kernel.org/stable/c/772cecf198da732faebb5dcfc46d66a505be8495
- https://git.kernel.org/stable/c/78069a6d8bc86c9e036eb82c2af4a19cc1871a53
- https://git.kernel.org/stable/c/8738b1b6d0e639ca1fc0f61516afd3557ac4ecc6
- https://git.kernel.org/stable/c/cd513e43b4b2bd1de39e2367bc4261c699a8652f
- https://git.kernel.org/stable/c/f08fb3d42fd3aad0b7a263da3ac3ebaf0845e265
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html
Original description
In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_exthdr: fix register tracking for F_PRESENT flag nft_exthdr_init() passes user-controlled priv->len to nft_parse_register_store(), which marks that many bytes in the register bitmap as initialized. However, when NFT_EXTHDR_F_PRESENT is set, the eval paths write only 1 byte (nft_reg_store8) or 4 bytes (*dest = 0 on TCP/DCCP error path). When len > 4, registers beyond the first are never written, retaining uninitialized stack data from nft_regs. Bail out if userspace requests too much data when F_PRESENT is set.
Last activity 6 Nov 2026. Patch Forecast updates every hour.