{ "file_item": { "filepath": "security-advisories", "filename": "CERT-EU-SA2022-018.pdf" }, "title": "Serious Vulnerability in Linux Kernel", "serial_number": "2022-018", "publish_date": "17-03-2022 09:28:00", "description": "On February 22, Red Hat released a security advisory for fixing a severe vulnerability in the \"netfilter\" subcomponent in the Linux kernel. Listed as CVE-2022-25636 with a CVSS score of 7.8, it could allow a local attacker with a user account on the system to gain access to out-of-bounds memory, leading to a system crash or a privilege escalation. This vulnerability is present in all recent major distributions and exploits for this vulnerability ware already published.
It is recommended to update the Linux distributions as soon as possible.", "url_title": "2022-018", "content_markdown": "---\ntitle: 'Serious Vulnerability in\u00a0Linux Kernel'\nversion: '1.0'\nnumber: '2022-018'\ndate: 'March 17, 2022'\n---\n\n_History:_\n\n* _17/03/2022 --- v1.0 -- Initial publication_\n\n# Summary\n\nOn February 22, Red Hat released a security advisory for fixing a severe vulnerability in the `netfilter` subcomponent in the Linux kernel. Listed as CVE-2022-25636 with a CVSS score of 7.8, it could allow a local attacker with a user account on the system to gain access to out-of-bounds memory, leading to a system crash or a privilege escalation [1]. This vulnerability is present in all recent major distributions and **exploits for this vulnerability ware already published** [2].\n\nIt is recommended to update the Linux distributions as soon as possible.\n\n# Technical Details\n\nAn out-of-bounds (OOB) memory access flaw was found in `nft_fwd_dup_netdev_offload` in `net/netfilter/nf_dup_netdev.c` in the `netfilter` subcomponent in the Linux kernel due to a heap out-of-bounds write problem [2]. \n\n# Affected Products\n\nThis vulnerability is present in the Linux kernel versions 5.4 through 5.6.10. on all major distributions such as Red Hat Enterprise Linux (RHEL) 8.x; Debian Bullseye; Ubuntu Linux, and SUSE Linux Enterprise 15.3 [3]. \n\nWhile the Linux kernel `netfilter` patch has been made available [4], the patch is not available yet in all distributions. \n\n\n# Recommendations and Mitigations\n\nCERT-EU recommends following the specific steps listed for each of the following Linux distributions:\n\n- Debian Bullseye, more details in [5];\n- Ubuntu releases, more details in [6];\n- Suse Linux Enterprise, more details in [7] and [8];\n- RedHat Hat Enterprise Linux more details in [9].\n\n# References\n\n[1] \n\n[2] \n\n[3] \n\n[4] \n\n[5] \n\n[6] \n\n[7] \n\n[8] \n\n[9] \n", "content_html": "

History:

  • 17/03/2022 --- v1.0 -- Initial publication

Summary

On February 22, Red Hat released a security advisory for fixing a severe vulnerability in the netfilter subcomponent in the Linux kernel. Listed as CVE-2022-25636 with a CVSS score of 7.8, it could allow a local attacker with a user account on the system to gain access to out-of-bounds memory, leading to a system crash or a privilege escalation [1]. This vulnerability is present in all recent major distributions and exploits for this vulnerability ware already published [2].

It is recommended to update the Linux distributions as soon as possible.

Technical Details

An out-of-bounds (OOB) memory access flaw was found in nft_fwd_dup_netdev_offload in net/netfilter/nf_dup_netdev.c in the netfilter subcomponent in the Linux kernel due to a heap out-of-bounds write problem [2].

Affected Products

This vulnerability is present in the Linux kernel versions 5.4 through 5.6.10. on all major distributions such as Red Hat Enterprise Linux (RHEL) 8.x; Debian Bullseye; Ubuntu Linux, and SUSE Linux Enterprise 15.3 [3].

While the Linux kernel netfilter patch has been made available [4], the patch is not available yet in all distributions.

Recommendations and Mitigations

CERT-EU recommends following the specific steps listed for each of the following Linux distributions:

  • Debian Bullseye, more details in [5];
  • Ubuntu releases, more details in [6];
  • Suse Linux Enterprise, more details in [7] and [8];
  • RedHat Hat Enterprise Linux more details in [9].

References

[1] https://access.redhat.com/security/cve/CVE-2022-25636

[2] https://nickgregory.me/linux/security/2022/03/12/cve-2022-25636/

[3] https://www.zdnet.com/article/nasty-linux-netfilter-firewall-security-hole-found/

[4] https://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf.git/commit/?id=b1a5983f56e371046dcf164f90bfaf704d2b89f6

[5] https://security-tracker.debian.org/tracker/CVE-2022-25636

[6] https://ubuntu.com/security/CVE-2022-25636

[7] https://www.suse.com/security/cve/CVE-2022-25636.html

[8] https://www.suse.com/support/kb/doc/?id=000020615

[9] https://access.redhat.com/security/cve/CVE-2022-25636

", "licence": { "title": "Creative Commons Attribution 4.0 International (CC-BY 4.0)", "link": "https://creativecommons.org/licenses/by/4.0/", "restrictions": "https://cert.europa.eu/legal-notice", "author": "The Cybersecurity Service for the Union institutions, bodies, offices and agencies" } }