CVE-2021-34527

Leaky Vessels was a set of container-escape vulnerabilities disclosed on 31 January 2024 by Rory McNamara of Snyk Security Labs, the headline flaw being CVE-2024-21626 (CVSS 8.6, runc 1.1.11 and earlier). It was an order-of-operations file-descriptor leak in runc's handling of the process working directory (WORKDIR / process.cwd). During container setup runc left an internal file descriptor referencing the host filesystem namespace open before all privileged descriptors were closed, so a malicious image or a build using a malicious Dockerfile or upstream FROM could set the working directory to that leaked descriptor via a path like /proc/self/fd/7. Because chdir occurred before the descriptor was closed, the container process gained a working directory in the host filesystem and could read and write host files, breaking container isolation and escaping to the underlying host. Related Docker BuildKit issues were disclosed alongside it: CVE-2024-23651 (mount cache race), CVE-2024-23652 (build-time arbitrary delete), and CVE-2024-23653 (GRPC SecurityMode privilege check bypass). The flaw was fixed in runc 1.1.12.

On 24 May 2023 Dig Security disclosed a privilege-escalation chain in Google Cloud SQL for SQL Server, originally reported to Google in February 2023, that let an attacker escalate from a limited database role to full system administrator and reach the host operating system. The chain first abused a gap in GCP's security hardening to add the attacker's user to DbRootRole, an elevated GCP admin role that nonetheless lacked full SQL Server permissions, then exploited a further misconfiguration in the role permission architecture to grant the SQL Server sysadmin role and obtain complete control of the database engine. With sysadmin rights the researchers reached the underlying container and host OS, letting them list privileged paths, read sensitive files and extract secrets, including internal GCP data and credentials related to the managed service. This was a provider-side flaw under shared responsibility that customers could not patch; Google remediated it in April 2023 and it was found and reported by researchers with no evidence of exploitation in the wild.

On 9 September 2021 Palo Alto Unit 42 researcher Yuval Avrahami disclosed Azurescape, described as the first cross-account container takeover in a public cloud, in which a malicious container on Azure Container Instances could escape and gain control over other customers' containers running on the shared multitenant Kubernetes cluster. ACI ran an outdated container runtime, runC v1.0.0-rc2, which was vulnerable to CVE-2019-5736, letting the attacker break out of the container and execute code as root on the underlying Kubernetes node. From the node the researcher found the bridge pod, which serviced az container exec calls, sent a Kubernetes service-account token in the Authorization header to a Kubelet that also allowed anonymous access; decoding that token (related to CVE-2018-1002102) granted pods/exec rights across all namespaces and control of the api-server, and thus the whole multitenant cluster. This was a provider-side flaw under shared responsibility that customers could not patch; Unit 42 found it and reported it with no knowledge of exploitation in the wild.

In 2019, a former Amazon engineer stole the personal data of about 100 million Americans from Capital One, and she did it through a chain of cloud-security mistakes that has since become a teaching classic. A misconfigured web application firewall could be tricked into making requests on the attacker's behalf, a flaw called server-side request forgery. She pointed it at a special internal address that every AWS server can reach, the one that hands out the server's temporary cloud credentials, grabbed those credentials, and because they were far more powerful than they needed to be, used them to download Capital One's data straight out of its storage. It is the textbook SSRF-to-cloud-takeover chain, and the reason AWS hardened that metadata service afterward.

usbliter8, published on 18 June 2026 by a research group called Paradigm Shift, is an unpatchable BootROM exploit for Apple's A12 and A13 chips, the silicon inside the iPhone XS, XR and 11 families plus the Apple Watch Series 4 and 5. It is the long-awaited successor to checkm8, the 2019 exploit that broke every Apple chip from the A5 to the A11 and was assumed to be the end of that road. The bug lives in the SecureROM, the very first code an Apple device runs at power on, which is etched into the silicon at the factory and can never be altered by any software update. usbliter8 abuses a hardware flaw in the Synopsys DWC2 USB controller: a mismatch in how the controller tracks its DMA memory while buffering USB Setup packets lets an attacker walk a write pointer backwards through memory and overwrite arbitrary SRAM, ending in full code execution inside the most trusted code on the chip. From there it can boot unsigned firmware and step outside Apple's chain of trust entirely, stamping the string PWND into the device's USB serial number as proof of control. The catch is that it is not a remote attack: it needs physical possession of the device, DFU recovery mode, a USB connection and a small RP2350 microcontroller board, and nothing it changes survives a reboot. It also does not break the Secure Enclave, so a device protected by a strong passcode keeps its user data encrypted even after the boot chain has been taken over. Apple cannot repair the affected chips; the only real remedy is newer hardware, because the A14 and later configure the controller correctly and are out of reach.

Copy Fail (CVE-2026-31431), disclosed on 29 April 2026 by the security firm Theori, is a Linux kernel flaw that turns any unprivileged local user into root with a 732-byte Python script and no luck required. Despite a name that sounds like a clipboard bug, it has nothing to do with copy and paste: it is a failed copy deep in the kernel's crypto code. A nine-year-old optimization in the AF_ALG crypto socket interface let an attacker steer the kernel into writing four attacker-chosen bytes into the page cache, the in-memory copy of files that the CPU actually executes. Patch the cached pages of a setuid-root binary like /usr/bin/su, run it, and you are root. The exploit is a straight-line logic flaw with no race condition and no hardcoded kernel addresses, so the exact same script runs at roughly 100 percent reliability across Ubuntu, RHEL, SUSE, Amazon Linux and every other distribution built since 2017. Worse, because the page cache is shared by the whole machine, it crosses container boundaries: one poisoned page in a Kubernetes pod can compromise neighbouring tenants and the host. The disk file is never touched, so file-integrity scanners stay silent. It rates CVSS 7.8 (High), was added to CISA's Known Exploited Vulnerabilities catalog on 1 May 2026, and is notable for how it was found: an AI-assisted code scan surfaced a bug that had been silently exploitable for nearly a decade in about one hour.