In the Linux kernel, the following vulnerability has been resolved:
sctp: handle the error returned from sctp_auth_asoc_init_active_key
When it returns an error from sctp_auth_asoc_init_active_key(), the active_key is actually not updated. The old sh_key will be freeed while it's still used as active key in asoc. Then an use-after-free will be triggered when sending patckets, as found by syzbot:
sctp_auth_shkey_hold+0x22/0xa0 net/sctp/auth.c:112 sctp_set_owner_w net/sctp/socket.c:132 [inline] sctp_sendmsg_to_asoc+0xbd5/0x1a20 net/sctp/socket.c:1863 sctp_sendmsg+0x1053/0x1d50 net/sctp/socket.c:2025 inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:819 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:734
This patch is to fix it by not replacing the sh_key when it returns errors from sctp_auth_asoc_init_active_key() in sctp_auth_set_key(). For sctp_auth_set_active_key(), old active_key_id will be set back to asoc->active_key_id when the same thing happens.
| Software | From | Fixed in |
|---|---|---|
| linux / linux_kernel | 4.19.199 | 4.19.262 |
| linux / linux_kernel | 5.4.136 | 5.4.220 |
| linux / linux_kernel | 5.10.54 | 5.10.150 |
| linux / linux_kernel | 5.13.6 | 5.14 |
| linux / linux_kernel | 5.14.1 | 5.15.75 |
| linux / linux_kernel | 5.16 | 5.19.17 |
| linux / linux_kernel | 6.0 | 6.0.3 |
| linux / linux_kernel | 5.14 | 5.14.x |
| linux / linux_kernel | 5.14-rc3 | 5.14-rc3.x |
| linux / linux_kernel | 5.14-rc4 | 5.14-rc4.x |
| linux / linux_kernel | 5.14-rc5 | 5.14-rc5.x |
| linux / linux_kernel | 5.14-rc6 | 5.14-rc6.x |
| linux / linux_kernel | 5.14-rc7 | 5.14-rc7.x |
A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.
CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.
A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.
Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.
Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.
SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.