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AWS Systems Manager Agent Vulnerability Allows Attackers to Bypass Port-Forwarding Restrictions

Critical SSRF flaw in AWS SSM Agent (CVE-2026-89049) lets authenticated users bypass link-local denylists and reach EC2 Instance Metadata Service for IAM credentials.

CVE-2026-89049 (Critical, CVSS v3.1 AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H) affects Amazon SSM Agent versions earlier than 3.3.4851.0, with the fix shipping in 3.3.4851.0. The remote-host port-forwarding feature's denylist for link-local addresses can be bypassed because equivalent address representations are not validated, enabling SSRF to restricted endpoints such as the EC2 Instance Metadata Service at 169.254.169.254. An attacker with authenticated AWS access and ssm:StartSession permission could retrieve instance profile IAM credentials and pivot to S3, Secrets Manager, Lambda, or other cloud resources depending on role permissions.

New DDRop Attack Breaks Intel TDX and AMD SEV-SNP With $159 DDR5 Device

DDRop uses a $159 DDR5 RDIMM interposer to silently drop memory writes and break Intel TDX and AMD SEV-SNP confidential VMs.

Researchers published DDRop, a physical attack built from about $159 in parts that uses a custom DDR5 RDIMM interposer to inject parity errors and silently discard selected cache-line writebacks. Intel TDX, Intel Scalable SGX, and AMD SEV-SNP are affected because they lack per-line cryptographic freshness, so processors can accept stale encrypted data as valid state. The team demonstrated deterministic plaintext copying between pages, malicious Secure EPT entry injection, forcing trust domains into debug mode, and forging attestation measurements. The attack requires privileged host control plus brief physical access, and researchers say no simple software patch exists.

Cyber Security News · 1d agoResearch 2 sources

DDRop Attack Forces Intel TDX Confidential VMs Into Debug Mode and Exposes Memory

KU Leuven and ETH Zurich researchers released DDRop PoC hardware that forces Intel TDX confidential VMs into debug mode and exposes plaintext memory.

Researchers from KU Leuven, ETH Zurich, Google, and Durham University published proof-of-concept code, hardware designs, and firmware for DDRop, a DDR5 interposer that injects parity errors to drop selected cache-line writebacks. Because Intel TDX, Intel Scalable SGX, and AMD SEV-SNP lack per-line cryptographic freshness, processors decrypt and accept stale DRAM contents as current state. The PoC flips a victim's ATTRIBUTES.DEBUG flag to enable TDX debug mode, then copies victim memory in plaintext and can forge attestation reports. Affected environments include Intel 5th- and 6th-generation Xeon Scalable with TDX; Intel says the attack falls outside its cloud-computing threat model.

GBHackers · 1d agoResearch

Hackers deploy Linux rootkit on F5 BIG-IP APM devices, hiding web shell in memory

Sophos analyzed a Linux rootkit, tracked as PoisonedRefresh, on hacked F5 BIG-IP APM devices hiding an in-memory web shell linked to exploited CVE-2025-53521.

Sophos and ESET analyzed an implant (named PoisonedRefresh by ESET) deployed on compromised F5 BIG-IP APM appliances, which serves enterprise, financial, government, and public sector deployments. The second-stage payload intercepts __libc_start_main, hooks Apache's APR module loader (apr_dso_load), RC4-encodes key strings, and rewrites PHP file reads in memory to embed a web shell inside legitimate scripts like apm_css.php3, full_wt.php3, and webtop_popup_css.php3, leaving on-disk files unchanged. A related installer component infects /usr/sbin/httpd, persists across BIG-IP upgrade images, modifies SELinux configuration, and deploys the payload. The malware also creates a Unix domain socket at /run/bigtlog.pipe that hands authenticated local connections to /bin/bash; F5 links the activity to CVE-2025-53521, an unauthenticated RCE in BIG-IP APM already exploited in the wild.

Help Net Security · 7d agoMalware in the wildCVE-2025-535211