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On July 22, Qualys published a Linux kernel advisory that anyone running shared hosting on a RHEL-family system should read before doing anything else: CVE-2026-64600, nicknamed RefluXFS. It is a local privilege escalation to root in the Linux kernel’s XFS filesystem, and the proof-of-concept Qualys published strips the root password from /etc/passwd in seconds — starting from an ordinary, unprivileged local account. The vulnerability has been sitting in the kernel since version 4.11, released in 2017. Nine years of shared hosting servers, VPS instances, and cloud nodes, quietly exposed. ...

F5 patched CVE-2026-42533 on July 15. If you run nginx, this one deserves your attention before the proof-of-concept code drops — and there is a countdown on that. What the flaw is The vulnerability is a heap buffer overflow (CWE-122) in nginx’s script engine — the component that assembles output strings from configuration directives at request time. It surfaces under a specific configuration pattern: a map block using regex matching, where the map’s output variable appears in a string expression after a numbered capture variable ($1, $2) from an earlier regex match. ...

Two weeks ago, on July 6, 2026, MariaDB Community Server 10.6 reached end of life. The MariaDB Foundation announced this back in June and gave people several months to plan. Some planned. Many did not. If you are in the second group, here is what you need to know. What “End of Life” Actually Means for a Database End of life does not make your database stop working. Queries keep returning rows, your application keeps humming along, and nothing explodes on day one. What stops is the flow of security patches, bug fixes, and corrective releases from the MariaDB Foundation. The 10.6 branch is now frozen. ...

A working proof-of-concept for CVE-2026-43499, nicknamed GhostLock, went public on July 7, 2026. It hands any unprivileged local user a root shell in about five seconds, and it works from inside a container to escape to the host. If you run Linux servers — shared hosting, VPS, or bare metal — this is the one to patch before anything else this week. What GhostLock is The bug lives in kernel/locking/rtmutex.c, on the futex priority-inheritance (PI) path. When the kernel handles a FUTEX_CMP_REQUEUE_PI requeue and detects a deadlock cycle, it rolls back with -EDEADLK by calling remove_waiter(). The problem: that helper clears pi_blocked_on on the wrong thread — not the sleeping thread it should be cleaning up, but the currently running task. That leaves a live thread holding a dangling pointer into already-freed kernel stack memory. Stack use-after-free. ...

PHP pushed maintenance releases for its two active development branches on July 1–2, 2026. PHP 8.5.8 and 8.4.23 are out. Neither is a major feature release, but they fix issues that can cause real harm to production servers. If you’re hosting PHP applications, patch now. The headliner: CVE-2026-14355 The most critical fix in both releases is CVE-2026-14355, addressing memory corruption in openssl_encrypt() when used with the AES-WRAP-PAD cipher mode (bug GH-22187). Specifically, the internal zend_mm_heap gets corrupted during this operation. Heap corruption is the kind of bug that ranges from “your process crashes at random” to “someone potentially executes arbitrary code,” depending on how the application uses the function and what an attacker can control. If you use PHP’s OpenSSL extension for encryption — and many applications do — this one warrants immediate attention. ...

On June 25, 2026, JFrog Security Research published a working exploit walkthrough for a Linux kernel privilege escalation they named DirtyClone. Tracked as CVE-2026-43503 with a CVSS score of 8.8, it lets any local user on an unpatched system escalate to root — and the attack leaves nothing on disk for forensic tools to find. That combination should get a hosting operator’s attention. What the Bug Is The flaw lives in __pskb_copy_fclone(), a kernel function that copies network packets internally. When a packet is cloned, this function — and a handful of related fragment-transfer helpers — drops a safety flag called SKBFL_SHARED_FRAG. That flag marks packet memory as shared with a file on disk. Once it’s gone, the kernel no longer treats the memory as read-only, and an attacker can write to it. ...

In May 2026, the IETF quietly did something that email administrators have been waiting on for years: they published RFC 9989, RFC 9990, and RFC 9991 — collectively known as DMARCbis. These three documents replace RFC 7489, which has been the authoritative reference for DMARC since 2015. The headline change isn’t technical; it’s procedural. The original RFC 7489 was published as an Informational document, meaning it described what the industry was already doing, not what it was required to do. DMARCbis arrives as a Proposed Standard on the IETF Standards Track — the first formal step toward becoming an Internet Standard. In plain terms: DMARC just graduated from “strong industry recommendation” to “official protocol.” ...

If you’re running Exim on Debian or Ubuntu and haven’t patched in the past five weeks, there’s a reasonable chance your mail server is remotely exploitable by anyone who can open a TLS connection to port 25. No credentials required. No special tooling. Standard SMTP commands. CVE-2026-45185, nicknamed Dead.Letter, is a use-after-free vulnerability in Exim’s BDAT message parsing path. CVSS score: 9.8 Critical. Fixed in Exim 4.99.3, released May 12, 2026. If you haven’t checked your version since then, now would be a good time. ...

On June 4, 2026, the PHP team pushed two releases: PHP 8.4.22 and PHP 8.5.7, both routine bug-fix updates. Notice what’s missing: no 8.2 release, no 8.3 release. That’s not an oversight — it’s the lifecycle working as designed. Once a PHP branch exits active support, it receives security patches only when a qualifying CVE appears. Routine bug fixes stop. June was a bug-fix month, so 8.2 and 8.3 sat it out. ...

Apache HTTP Server 2.4.68 came out on June 8, 2026 — the first point release since 2.4.67 in early May, and per the project’s own download page, it’s “recommended over all previous releases.” If you run your own LAMP stack, this is the patch to schedule this week. What’s actually in it The public CVE list on httpd.apache.org hasn’t fully caught up to the release yet, but the individual disclosures have already landed on oss-security and in distro security trackers. Three are worth knowing about specifically. ...