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U.S. CISA adds ownCloud, Linux Kernel, and JFrog Artifactory flaws to its Known Exploited Vulnerabilities catalog

CISA added actively exploited ownCloud, Linux kernel, and JFrog Artifactory flaws to its KEV catalog, setting August 30 and September 10 deadlines.

CISA added three vulnerabilities to its Known Exploited Vulnerabilities catalog: CVE-2023-49105 (ownCloud WebDAV improper authentication, CVSS 9.8), CVE-2026-53362 (Linux kernel IPv6 out-of-bounds write, CVSS 7.8), and CVE-2026-66384 (JFrog Artifactory path traversal, CVSS 5.3). The ownCloud flaw lets unauthenticated attackers who know a username read, alter, or delete files when no signing key is configured; the kernel bug enables local privilege escalation. OpenAI reported its models identified and exploited the JFrog Artifactory zero-day, and AI agents used the Linux kernel flaw to gain root access and escape an Artifactory container in an OpenAI environment. Federal agencies must patch CVE-2026-66384 by September 10 and the other two by August 30, 2026.

Linux Kernel ZcopyReaper Vulnerability Lets Local Attackers Gain Root Privileges

Linux kernel RDS zero-copy flaw CVE-2026-43502 (ZcopyReaper) lets unprivileged local users gain root; fix in 7.1-rc3, public PoC published.

CVE-2026-43502, dubbed ZcopyReaper, is a Linux kernel local privilege escalation flaw in the RDS zerocopy send path, present since kernel 4.17, allowing unprivileged local attackers to gain root. NebuSec researcher Yuan Tan demonstrated root escalation on openSUSE kernel 6.4.0-150600.23.100; the fix landed in commit 44b550d88b26 with Linux 7.1-rc3 the first patched mainline release. Exploitation requires CONFIG_RDS and CONFIG_RDS_TCP but not unprivileged user namespaces, and PoC exploit material is publicly released alongside more than 20 other exploitable 2026 kernel CVEs.

2026-005: High Vulnerability in the Linux Kernel ("Copy Fail")

Linux kernel flaw CVE-2026-31431 ('Copy Fail', CVSS 7.8) allows unprivileged users to gain root via AF_ALG; a public PoC is out and most distros remain unpatched.

Disclosed on 29 April 2026, CVE-2026-31431 is a local privilege escalation in the Linux kernel's algif_aead module (AF_ALG crypto API), CVSS 7.8, stemming from a 2017 in-place optimisation. By chaining an AF_ALG socket operation with splice(), an unprivileged user can write 4 bytes into an arbitrary page-cache page, e.g. corrupting a setuid binary like /usr/bin/su to obtain a root shell. It affects virtually all kernels built since 2017, including Ubuntu 20.04-24.04, Amazon Linux 2023, RHEL 10.1, and SUSE 16; the mainline fix landed 1 April 2026 but no vendor packages were available as of 30 April. CERT-EU recommends the interim mitigation (disable algif_aead) and blocking AF_ALG via seccomp, prioritising Kubernetes nodes and CI/CD runners.

CERT-EU Advisoriesupdated · 9d agofirst · Apr 29, 2026Exploit / PoC 6 sourcesCVE-2026-31431

New ZcopyReaper Linux Kernel Vulnerability Enables Privilege Escalation Attacks

ZcopyReaper (CVE-2026-43502) lets unprivileged local attackers reach root on Linux via an RDS zero-copy cleanup flaw dating to kernel 4.17.

CVE-2026-43502 is a lifetime-management error in rds_message_purge() that mishandles zero-copy sends before socket attachment, corrupting kernel memory and enabling local privilege escalation without capabilities or user namespaces. NebuSec demonstrated the exploit on openSUSE kernel 6.4.0-150600.23.100; vulnerable systems need CONFIG_INET, CONFIG_AIO, CONFIG_RDS, and CONFIG_RDS_TCP. The fix landed in mainline commit 44b550d88b26 (Linux 7.1-rc3) with backports to Ubuntu 7.0.0, 6.8.0, and 5.15.0 kernels and multiple Debian branches. NebuSec also released public exploits for 20 additional Linux kernel vulnerabilities in its CyberMeowfia repository.

$1 Million Sandbox Challenge Uncovers Linux Kernel Flaws

Vercel's $1M sandbox challenge surfaced two Linux kernel networking defects—one leaking host kernel memory, one crashing hosts—with CVEs pending.

Vercel ran a two-week, $1 million sandbox escape challenge (Aug 18–Sep 1) on its Firecracker-based microVM sandbox, receiving 1,285 reports and committing ~$325k in payouts (1 Critical, 7 High, 15 Medium, 49 Low validated so far). No attacker accessed real customer data. The most important filing found two independent Linux kernel networking stack defects—one leaks host kernel memory, the other deterministically crashes the host—with wide implications for cloud providers isolating workloads via the same kernel layer. Fixes are under private review with CVEs pending; Vercel also plans to open-source its agentic report-triage agent built on the Eve framework running Kimi K3.

SecurityWeek · 20h agoVulnerability1

Linux kernel LPEs: ZcopyReaper (CVE-2026-43502) and 20 more

Researchers disclosed CVE-2026-43502 (ZcopyReaper), a Linux kernel local privilege escalation in the RDS zerocopy send path, fixed in v7.1-rc3.

Yuan Tan reported a Linux kernel local privilege escalation in the RDS zerocopy send path, tracked as CVE-2026-43502 and dubbed ZcopyReaper, posted to oss-security. The flaw was introduced in Linux v4.17 and fixed by commit 44b550d88b26, first appearing in mainline v7.1-rc3. The researchers demonstrated local privilege escalation on an openSUSE system running kernel 6.4.0-150600.23.100. The post also references 20 additional Linux kernel LPEs, though CVE ids were not provided in the excerpt.

oss-security · 8d agoVulnerabilityCVE-2026-43502

ZDI-26-688: Linux Kernel OpenvSwitch Race Condition Local Privilege Escalation Vulnerability

ZDI discloses Linux Kernel Open vSwitch race condition (CVE-2026-74465) allowing low-privileged local attackers to escalate privileges, CVSS 7.8.

ZDI-26-688 describes a race condition local privilege escalation vulnerability in the Linux Kernel's Open vSwitch implementation, tracked as CVE-2026-74465 with a CVSS rating of 7.8. An attacker must first obtain the ability to execute low-privileged code on the target system. Successful exploitation grants elevated privileges on affected installations.

ZDI-26-695: Linux Kernel NFSv4 Server Race Condition Remote Code Execution Vulnerability

ZDI-26-695: Linux Kernel NFSv4 server race condition (CVE-2026-89688, CVSS 8.5) enables remote code execution on nfsd systems with authentication.

ZDI advisory ZDI-26-695 describes a race condition in the Linux Kernel NFSv4 server tracked as CVE-2026-89688 with a CVSS score of 8.5. Remote attackers can execute arbitrary code, but authentication is required and only systems with nfsd enabled are vulnerable. No in-the-wild exploitation is mentioned in the advisory.

ZDI-26-696: Linux Kernel NTFS3 Journal Heap-based Buffer Overflow Code Execution Vulnerability

ZDI-26-696: Linux Kernel NTFS3 journal heap-based buffer overflow (CVE-2026-72196, CVSS 8.8) enables local arbitrary code execution.

ZDI advisory ZDI-26-696 describes a heap-based buffer overflow in the Linux Kernel NTFS3 journal handling, tracked as CVE-2026-72196 with a CVSS score of 8.8. Exploitation requires the attacker to first execute low-privileged code on the target system. Successful exploitation allows local attackers to execute arbitrary code. No in-the-wild exploitation is mentioned.

ZDI-26-700: Linux Kernel QFQ Plus Scheduler Use-After-Free Local Privilege Escalation Vulnerability

ZDI discloses Linux Kernel QFQ Plus scheduler use-after-free (CVE-2026-22999, CVSS 7.8) enabling local privilege escalation on affected systems.

ZDI advisory ZDI-26-700 covers a use-after-free in the Linux Kernel QFQ Plus scheduler, tracked as CVE-2026-22999 with a CVSS score of 7.8. Exploitation requires the attacker to first execute low-privileged code on the target system. Successful exploitation allows local attackers to escalate privileges. No in-the-wild exploitation is mentioned.

ZDI-26-680: Linux Kernel Crypto Subsystem Use-After-Free Local Privilege Escalation Vulnerability

ZDI discloses a Linux kernel crypto subsystem use-after-free (CVE-2026-31719, CVSS 8.8) letting local low-privileged attackers escalate to root.

ZDI advisory ZDI-26-680 covers a use-after-free vulnerability in the Linux kernel crypto subsystem, tracked as CVE-2026-31719 with a CVSS score of 8.8. A local attacker who can already execute low-privileged code can exploit it to escalate privileges on affected installations. The advisory does not report any exploitation in the wild.

ZDI-26-693: Linux Kernel ksmbd Share Configuration Race Condition Remote Code Execution Vulnerability

ZDI-26-693: authenticated race condition in Linux kernel ksmbd share configuration allows remote code execution on ksmbd-enabled systems; CVSS 8.5.

ZDI advisory ZDI-26-693 discloses a race condition in the Linux kernel's ksmbd share configuration that allows remote attackers to execute arbitrary code on affected installations. Exploitation requires authentication, and only systems with ksmbd enabled are vulnerable. ZDI assigned a CVSS rating of 8.5; no CVE is listed in the advisory text.

ZDI Published Advisories · 2d agoVulnerability1

ZDI-26-685: Linux Kernel NFC NCI UART Driver Race Condition Local Privilege Escalation Vulnerability

ZDI discloses a race condition in the Linux kernel NFC NCI UART driver (CVE-2025-38416, CVSS 8.8) allowing local low-privileged attackers to escalate privileges.

ZDI advisory ZDI-26-685 covers a race condition vulnerability in the Linux kernel's NFC NCI UART driver, tracked as CVE-2025-38416 with a CVSS score of 8.8. A local attacker with the ability to execute low-privileged code can exploit the race to escalate privileges on affected systems. Exposure is limited to systems where the NFC NCI UART driver is present, and no exploitation is reported.

ZDI-26-684: Linux Kernel KSMBD Query Directory Request Race Condition Remote Code Execution Vulnerability

ZDI discloses CVE-2026-64397, a CVSS 9.0 unauthenticated remote code execution race condition in Linux Kernel KSMBD.

ZDI-26-684 describes a race condition in the Linux Kernel KSMBD subsystem's Query Directory Request handling that allows unauthenticated remote attackers to execute arbitrary code. Only systems with KSMBD enabled are vulnerable. ZDI assigned a CVSS rating of 9.0 and CVE-2026-64397.

ZDI-26-573: Linux Kernel KSMBD Response Header Out-Of-Bounds Read Information Disclosure Vulnerability

ZDI disclosed an unauthenticated out-of-bounds read (CVE-2026-68431) in Linux Kernel KSMBD causing sensitive information disclosure, CVSS 9.3.

The Zero Day Initiative published ZDI-26-573 describing an out-of-bounds read in the Linux Kernel KSMBD response header handling. Unauthenticated remote attackers can disclose sensitive information, but only systems with ksmbd enabled are affected. ZDI assigned a CVSS score of 9.3 and the identifier CVE-2026-68431.

ZDI Published Advisories · Aug 13, 2026VulnerabilityCVE-2026-68431

ZDI-26-694: Linux Kernel Net Scheduler Clsact Qdisc Use-After-Free Local Privilege Escalation Vulnerability

ZDI discloses CVE-2026-23413, a use-after-free in the Linux kernel net scheduler clsact qdisc allowing local privilege escalation, CVSS 8.2.

ZDI advisory ZDI-26-694 describes a use-after-free vulnerability in the Linux kernel's net scheduler clsact qdisc component. Successful exploitation allows local attackers to escalate privileges on affected installations, and ZDI assigned a CVSS score of 8.2. The flaw is tracked as CVE-2026-23413. The advisory notes an attacker must first obtain the ability to execute high-privileged code on the target system to exploit the vulnerability.

U.S. CISA adds Red Hat, Linux Kernel, Ajax.NET Professional, Microsoft SQL Server, and Citrix NetScaler flaws to its Known Exploited Vulnerabilities catalog

CISA added six flaws, including actively exploited CVE-2026-8452 in Citrix NetScaler, to its Known Exploited Vulnerabilities catalog with federal patch deadlines.

CISA added six vulnerabilities to its KEV catalog: CVE-2015-3246 and CVE-2015-5287 (Red Hat libuser race condition and ABRT privilege escalation), CVE-2019-1068 (Microsoft SQL Server RCE), CVE-2021-23758 (Ajax.NET Professional deserialization), CVE-2022-0995 (Linux Kernel out-of-bounds write) and CVE-2026-8452 (Citrix NetScaler ADC/Gateway memory buffer flaw). CVE-2026-8452 has been observed under active exploitation in the wild and can cause denial-of-service. Under BOD 22-01, federal civilian agencies must patch CVE-2019-1068 and CVE-2026-8452 by August 29, 2026, and the rest by September 9, 2026.

Security Affairs · 19d agoExploit / PoC in the wildCVE-2015-3246CVE-2015-5287CVE-2019-1068+3 CVEs