Security Week 2644: Active Exploitation of PHP2Shell Vulnerabilities Confirmed
Security Week 2644 highlights the active exploitation of PHP2Shell vulnerabilities, the most significant development of the previous week. On Tuesday, October 20, PHP developers announced patches for CVE-2026-109618 and CVE-2026-109619. Updates were issued the following day for supported branches PHP 8.2ā8.5 and unsupported versions including PHP 7.4, 8.0, and 8.1, along with partial mitigations for organizations unable to update immediately.
Both vulnerabilities theoretically enable arbitrary code execution on the server without authentication. The window between patch publication and active exploitation proved longer than the anticipated 15 minutes, although some organizations preemptively disabled government websites. Amazon reported exploitation attempts four days before the official patches. Confirmed attacks with functional exploits began only on Sunday, October 25.
The coordinated disclosure process remains critical for widely used software. The rise of AI-assisted vulnerability research has increased the speed of both discovery and exploit development, reducing the traditional delay between patch release and weaponization. CrowdStrike reported on October 23 that practical exploitation of the PHP issues in real attacks faced objective technical challenges.
Exploitation has now begun, and administrators must update vulnerable servers urgently. As of October 25, only one-fifth of the top 10,000 Russian websites were confirmed to run patched PHP versions. Kaspersky Lab issued recommendations for both corporate clients and home users, noting that the bugs also affect consumer NAS devices and server software such as Unraid and Nextcloud.
Other notable incidents
Indian certificate authority eMudhra suffered a major compromise after generating eight intermediate certificates with private keys as short as 3 to 8 bits instead of the required 384 bits. The incident triggered a widespread revocation campaign, ultimately leading the company to cease operations as a certificate authority.
Additional reports covered safe deployment of AI tools in enterprise environments, renewed activity involving the BlackLotus bootkit, and new operations by the Lazarus group. The Zero Day Initiative accidentally disclosed Linux kernel vulnerabilities to the public Linux Kernel Mailing List. Eye Security took control of 15 domains to distribute a patch for the abandoned Time4Popcorn software, preventing mass compromise via its update mechanism.
A critical, 10-point vulnerability (CVE-2026-110264) was discovered in GitLabās Regular Expression Compiler component, enabling arbitrary code execution. A 16-year-old flaw was also identified in Broadcom routers commonly used by ISPs, while critical issues were fixed in the nginx web server.
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