Hispasec•September 11, 2026•🇪🇸Translated from Spanish

Attackers Chain JFrog Artifactory CVEs for Rapid Admin Takeover and Backdoor Deployment

Real-world attacks against self-hosted JFrog Artifactory have combined several CVEs to move from unauthenticated requests to administrator privileges. The objective extends beyond initial access: attackers establish persistence, deploy backdoors, and open the door to potential software supply chain compromise.

Between 15 August and 8 September 2026, multiple self-hosted JFrog Artifactory instances received attacks that resulted in administrative control, creation of persistent accounts, and deployment of backdoors. The timeframe is significant because these were not isolated proof-of-concept attempts but complete intrusions that, in some cases, progressed from initial access to a new administrator account in under five minutes.

The primary attack path relies on chaining CVE-2026-42018 and CVE-2026-42016. The flaw CVE-2026-42018 allows an attacker to obtain an internal token associated with the anonymous user without logging in, even when anonymous access is disabled. Using this foothold, CVE-2026-42016 enables conversion of a low-privilege token into one with administrator scope because the validation checks only signature and issuer, not the actual token scope. This escalation has an additional side effect: certain administrative actions may appear in logs as token:anonymous rather than a named account, complicating forensic analysis.

Attackers then leveraged the Artifactory plugin ecosystem to solidify their presence. Malicious Groovy plugins were installed through the plugin framework, enabling server-side code execution. From there, shell commands were executed via a plugin execution endpoint for reconnaissance and file enumeration. A dropper downloaded a binary over HTTP, wrote it to globally writable paths such as /tmp, and opened a command-and-control channel. In several cases the deployment culminated in a Rust backdoor for remote control.

In parallel, CVE-2026-82329 was exploited independently between 1 and 8 September 2026. This critical authentication bypass flaw, rated CVSS 9.8, allows administrative privileges without chaining other defects and primarily affects default configurations of self-hosted Artifactory. Observed exploitation included creation of administrator tokens and enumeration of users, groups, and credential sets.

Priority must be given to patching. Fixes for CVE-2026-82329 are available in versions 7.111.21, 7.117.28, 7.125.20, 7.133.29, 7.146.38 and 7.161.20. For the CVE-2026-42018 plus CVE-2026-42016 chain, correcting at least one of the two vulnerabilities is sufficient to break the attack, although applying all available updates is recommended, especially for internet-exposed instances.

If immediate patching is not possible, a quick mitigation for CVE-2026-82329 is to configure an extra random join key in system.yaml. Organizations should still treat exposed servers as potentially compromised: review audit logs for administrative actions linked to token:anonymous and new high-privilege accounts, rotate exposed credentials and tokens, and audit changes to users, groups, and federated access topologies. Additional steps include inspecting for unauthorized Groovy plugins, checking file systems and scheduled tasks for binaries in paths such as /tmp, and verifying integrity of critical repositories and artifacts to protect the CI/CD pipeline.

Related articles

Habr•Vulnerabilities & Exploits

Six Months After tun0 Leak: Which Android VPN Clients Fixed Server Address Exposure and Which Ignored It

A detailed investigation reveals that Android VPN clients suffer from two distinct server address leaks when split tunneling is enabled. The first leak, tied to an unprotected local SOCKS proxy on 127.0.0.1, was quickly mitigated by most Xray and sing-box based clients through random ports and passwords. The second, more persistent leak allows excluded applications to bind sockets directly to the tun0 interface and discover the VPN server IP without root or special permissions. Only TeapodStream and OlConnect implemented owner-UID checks using ConnectivityManager.getConnectionOwnerUid, yet both initially mishandled the INVALID_UID response returned for excluded apps. AmneziaVPN has unmerged pull requests that correctly reject unknown owners, while sing-box offers a manual package_name_regex rule. v2rayNG closed the report as not planned, and major clients including WireGuard for Android, Mullvad, Proton VPN and others have issued no statements.

Habr•Vulnerabilities & Exploits

Part 2: How Third-Party Developers Closed the tun0 Leak in AmneziaVPN on Android

Third-party contributors to AmneziaVPN have detailed their fix for a VPN tunnel bypass affecting excluded applications on Android. The vulnerability allows any app, even those disallowed from the VPN, to bind sockets directly to the tun0 interface using SO_BINDTODEVICE and thereby discover the VPN server address. The team implemented a packet filter inside the client that queries Android via ConnectivityManager.getConnectionOwnerUid to determine packet ownership and drops traffic from unknown UIDs. The solution was integrated into both the Xray and AmneziaWG traffic paths, with the AmneziaWG hook placed inside amneziawg-go after packet parsing. Testing with leak_probe.py showed zero successful bypass attempts out of six methods when the filter was active, compared to six out of six without it. The developers submitted three pull requests and released a side-loaded test build, while noting remaining limitations such as raw sockets and tethering scenarios.

BoletimSec•Vulnerabilities & Exploits

Cisco Confirms Active Exploitation of CVE-2026-76504 in Catalyst SD-WAN Manager

Cisco has confirmed that the critical vulnerability CVE-2026-76504 in Catalyst SD-WAN Manager has been exploited in attacks throughout September. The flaw carries a CVSS score of 9.8 and allows attackers to gain full administrator access without any credentials by bypassing API authentication through malformed URI encoding. The issue affects the login session handling mechanism, enabling forged requests to grant netadmin privileges by default. Similar URI manipulation techniques were observed earlier this month in Oracle PeopleSoft attacks. Patches are available across multiple release trains including 20.9.10.1, 20.12.8.2, 20.15.6.1, 20.18.4.1, 26.1.2.1 and 26.2.1, while older installations must migrate to supported versions. Cisco recommends restricting access to trusted hosts and placing the Manager behind firewalls until updates are applied. The vulnerability was discovered during routine support operations and verified by Cisco's Product Security Incident Response Team.

BoletimSec•Vulnerabilities & Exploits

Zero-Days in PaperCut MF Chained to Compromise Active Directory in Education Sector

Analysts at eSentire investigated an attack that chained two zero-days in PaperCut MF, tracked as CVE-2026-81578 and CVE-2026-82078, to move from an internet-exposed print server to a domain controller in an education sector client in under two days. Attackers gained initial access through the card or badge query field, delivering malicious Java code that allowed unauthenticated configuration changes and arbitrary bytecode execution on version 24.0.2. The first stage loader reassembled payload fragments in memory, launched the next stage, and deleted its own files while remaining compatible with multiple Tomcat versions. A web shell followed, accepting commands via a custom HTTP header, reading configurations, and erasing log traces while positioning itself early in the request processing chain. The command-and-control implant was AdaptixC2, hidden inside a modified Microsoft Copilot binary downloaded from Alibaba Cloud infrastructure. Privilege escalation was achieved without passwords by locating a domain-privileged service account, stealing its access token, and relaunching the implant under those rights. On the domain controller the payload arrived via administrative share and was executed by modifying the Windows PlugPlay service, after which the legitimate path was restored to minimize traces. The operators extracted credentials from memory and registry, enabled Restricted Admin mode, used an NTLM hash for RDP access, and copied the full Active Directory database containing passwords for all domain accounts.