TOM4TA

Cyber Security Professional - Splunk enthusiast, red teamer & pentester. Cisco, Microsoft, and ISC2 certified & a disaster recovery nerd | #InfoSec | #CyberSec

[BleepingComputer @BleepinComputer]

Microsoft confirms outage affecting MFA, My Sign-Ins platform
https://t.co/QlFAk6zupv

https://t.co/QlFAk6zupv

[BleepingComputer @BleepinComputer]

Microsoft warns of new Defender zero-days exploited in attacks
https://t.co/9y5WTlmHSb

https://t.co/9y5WTlmHSb

[BleepingComputer @BleepinComputer]

Dell confirms its SupportAssist software causes Windows BSOD crashes
https://t.co/yP5YOISVOn

https://t.co/yP5YOISVOn

[BleepingComputer @BleepinComputer]

Microsoft fixes Windows Autopatch bug installing restricted drivers
https://t.co/hyvuCFbMlh

https://t.co/hyvuCFbMlh

[BleepingComputer @BleepinComputer]

Microsoft fixes BitLocker recovery issue only for Windows 11 users
https://t.co/1exiKlDK8a

https://t.co/1exiKlDK8a

[BleepingComputer @BleepinComputer]

The attack on the Trellix source code repository disclosed last week has been claimed by the RansomHouse threat group, which leaked a small set of images as proof of the intrusion.

https://t.co/uDQuMJXewY

[BleepingComputer @BleepinComputer]

Ivanti warns of new EPMM flaw exploited in zero-day attacks
https://t.co/6iseXQaSEK

https://t.co/6iseXQaSEK

[Blue Team News @blueteamsec1]

New Cisco DoS flaw requires manual reboot to revive devices https://t.co/JDFfFE3D1h #Security

[BleepingComputer @BleepinComputer]

Palo Alto Networks warns of firewall RCE zero-day exploited in attacks
https://t.co/DDHx9m9n5n

https://t.co/DDHx9m9n5n

[BleepingComputer @BleepinComputer]

CISA says ‘Copy Fail’ flaw now exploited to root Linux systems
https://t.co/k2KdOQ6lve

https://t.co/k2KdOQ6lve

[BleepingComputer @BleepinComputer]

Microsoft confirms April Windows updates cause backup failures
https://t.co/brzQw6rsXL

https://t.co/brzQw6rsXL

[International Cyber Digest @IntCyberDigest]

‼️🚨 BREAKING: An AI found a Linux kernel zero-day that roots every distribution since 2017. The exploit fits in 732 bytes of Python. Patch your kernel ASAP.

The vulnerability is CVE-2026-31431, nicknamed "Copy Fail," disclosed today by Theori. It has been sitting quietly in the Linux kernel for nine years.

Most Linux privilege-escalation bugs are picky. They need a precise timing window (a "race"), or specific kernel addresses leaked from somewhere, or careful tuning per distribution. Copy Fail needs none of that. It is a straight-line logic mistake that works on the first try, every time, on every mainstream Linux box.

The attacker just needs a normal user account on the machine. From there, the script asks the kernel to do some encryption work, abuses how that work is wired up, and ends up writing 4 bytes into a memory area called the "page cache" (Linux's high-speed copy of files in RAM). Those 4 bytes can be aimed at any program the system trusts, like /usr/bin/su, the shortcut to becoming root.

Result: the next time anyone runs that program, it lets the attacker in as root.

What should worry most: the corruption never touches the file on disk. It only exists in Linux's in-memory copy of that file. If you imaged the hard drive afterwards, the on-disk file would match the official package hash exactly. Reboot the machine, or just put it under memory pressure (any normal system load that needs the RAM), and the cached copy reloads fresh from disk.

Containers do not help either. The page cache is shared across the whole host, so a process inside a container can use this bug to compromise the underlying server and reach into other tenants.

The original sin was a 2017 "in-place optimization" in a kernel crypto module called algif_aead. It was meant to make encryption slightly faster. The change broke a critical safety assumption, and nobody noticed for nine years. That bug then rode every kernel update from 2017 to today.

This vulnerability affects the following:
🔴 Shared servers (dev boxes, jump hosts, build servers): any user becomes root
🔴 Kubernetes and container clusters: one compromised pod escapes to the host
🔴 CI runners (GitHub Actions, GitLab, Jenkins): a malicious pull request becomes root on the runner
🔴 Cloud platforms running user code (notebooks, agent sandboxes, serverless functions): a tenant becomes host root

Timeline:
🔴 March 23, 2026: reported to the Linux kernel security team
🔴 April 1: patch committed to mainline (commit a664bf3d603d)
🔴 April 22: CVE assigned
🔴 April 29: public disclosure

Mitigation: update your kernel to a build that includes mainline commit a664bf3d603d. If you cannot patch immediately, turn off the vulnerable module:

echo "install algif_aead /bin/false" > /etc/modprobe.d/disable-algif.conf
rmmod algif_aead 2>/dev/null || true

For environments that run untrusted code (containers, sandboxes, CI runners), block access to the kernel's AF_ALG crypto interface entirely, even after patching. Almost nothing legitimate needs it, and blocking it shuts the door on this whole class of bug...

[BleepingComputer @BleepinComputer]

CISA orders feds to patch Windows flaw exploited as zero-day
https://t.co/ZDyoycWMcu

https://t.co/ZDyoycWMcu

[CyberScoop - @cyberscoop.bsky.social @CyberScoopNews]

U.S. and international government agencies warned Thursday about a “widespread shift” in Chinese hacker methods toward the use of large-scale covert networks that compromise common devices to carry out a variety of attacks. https://t.co/p5xFjmGFN6

[BleepingComputer @BleepinComputer]

Alleged Silk Typhoon hacker extradited to US for cyberespionage
https://t.co/ci0Cuw3yNF

https://t.co/ci0Cuw3yNF

[BleepingComputer @BleepinComputer]

Microsoft says https://t.co/rJOd3VbrUk outage is causing sign‑in failures
https://t.co/HpakL2nf2i

https://t.co/HpakL2nf2i

[BleepingComputer @BleepinComputer]

CISA has ordered U.S. federal agencies to patch a Microsoft Defender privilege escalation flaw (dubbed BlueHammer) that has been exploited in zero-day attacks.
https://t.co/isROAzx5Az

[BleepingComputer @BleepinComputer]

Veeam warns of critical flaws exposing backup servers to RCE attacks
https://t.co/aGvGnXH7Zp

https://t.co/aGvGnXH7Zp

[Nicolas Krassas @Dinosn]

Conduent data breach could be largest in U.S. history https://t.co/GnVW2E0B5r

[BleepingComputer @BleepinComputer]

CISA: VMware ESXi flaw now exploited in ransomware attacks - @serghei
https://t.co/nrYhVs3GQM

https://t.co/nrYhVs3GQM