Loading vulnerability…
CVE-2026-43233 is an out-of-bounds read vulnerability in the Linux kernel netfilter H.323 connection-tracking helper, specifically in nf_conntrack_h323's decode_choice() routine. The flaw arises because the boundary check performed before calling get_len() uses the local variable len while it is still zero-initialized, rather than validating that sufficient bytes remain for get_len() to read. In the affected code path, when the PER bitstream has been consumed exactly, the boundary check incorrectly succeeds and get_len() dereferences past the end of the buffer, reading one byte beyond the buffer boundary and potentially a second byte depending on the high bit of the first over-read byte. The issue can be triggered by a crafted Q.931 SETUP message carrying a User-User Information Element with specially formed PER-encoded data, causing a heap-buffer-overflow read in kernel memory during H.323 message parsing.
Mallory correlates every CVE against your assets, your vendors, and active adversary campaigns. Know which vulnerabilities matter for you, not just which ones are loud.
What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.
What an attacker gets, and what they’ve been doing with it.
If you can’t patch tonight, do this now.
Patch, then assume compromise.
No public exploits tracked yet. Mallory keeps watching.
No public exploit code observed for this vulnerability.
Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.
Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.
2 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
A specific vulnerability affecting Red Hat Enterprise Linux 9 kernel-related packages, referenced in RHSA-2026:57252.
Linux kernel netfilter nf_conntrack_h323 out-of-bounds read in decode_choice().
Query your assets running an affected version, and investigate the blast radius.
Every observed campaign linking this CVE to a named adversary.
Malware families riding this exploit, with evidence and IOCs.
YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.
Cross-references every affected SKU, including bundled OEM variants.
Community discussion across Reddit, Mastodon, and other social sources.