PCPJack — modular cloud-credential-theft worm chaining 5 public CVEs; evicts TeamPCP

UPDATE (originally covered 2026-05-13, 2026-05-15): Three concurrent developments show the TeamPCP / Shai-Hulud campaign has entered an open-source-imitator phase following Datadog Security Labs' 2026-05-13 analysis of the leaked Shai-Hulud worm source code. First, OX Security disclosed on 2026-05-17 four malicious npm packages published by deadcode09284814 — chalk-tempalte, @deadcode09284814/axios-util, axois-utils, and color-style-utils — combined weekly downloads ~3,000 (OX Security, 2026-05-17; The Hacker News, 2026-05-18). chalk-tempalte is a near-unmodified clone of the leaked Shai-Hulud worm with a modified C2 server and a new attacker-controlled key embedded in the code — the two primary sources disagree on whether this is a public or private key (see § 7); axois-utils bundles "Phantom Bot," a Golang HTTP/TCP/UDP/Reset-flood DDoS tool with Windows Startup folder and Linux scheduled-task persistence that survives package removal; the other two harvest SSH keys, cloud-provider credentials (AWS/GCP/Azure), and cryptocurrency wallet data.

Second, SANS ISC synthesised a 2026-05-18 campaign update confirming that Checkmarx officially acknowledged on 2026-05-11 that its Jenkins AST Scanner plugin had been trojanised — version 2026.5.09, compromise window 2026-05-09 01:25 UTC to 2026-05-10 08:47 UTC — making this TeamPCP's third confirmed Checkmarx intrusion in three months (SANS Internet Storm Center, 2026-05-18; Checkmarx, 2026-05-12). Hundreds of Jenkins controllers installed the malicious plugin before removal; remediated builds 2.0.13-848 and 2.0.13-847 are safe. CxSAST on-premise was unaffected; the cloud-integrated checkmarx/ast-github-action, checkmarx/kics-github-action, and VS Code extensions were all trojaned.

Third, SentinelLabs disclosed on 2026-05-07 — also folded into the SANS ISC summary — "PCPJack," a rival cloud worm that scans for exposed Docker, Kubernetes, Redis, MongoDB and RayML services and chains five CVEs (CVE-2025-29927 Next.js middleware auth bypass; CVE-2025-55182 Next.js Server Actions deserialization; CVE-2026-1357 WPVivid arbitrary file upload; CVE-2025-9501 W3 Total Cache RCE; CVE-2025-48703 CentOS Web Panel command injection) for initial access, then explicitly kills TeamPCP processes and removes TeamPCP artefacts before harvesting credentials — assessed by SentinelLabs with moderate confidence as possibly a former TeamPCP affiliate. Defender takeaway for the Swiss/EU public-sector SOC: developer endpoints and CI/CD runners with installed Checkmarx plugin should be audited for plugin versions outside the known-safe SHA range during the 2026-05-09 → 2026-05-10 window; npm audit and SBOM scans should flag the deadcode09284814 author/scope; egress from CI runners to *.lhr.life hostnames is a high-fidelity hunt pivot for the npm worm wave; Docker/Kubernetes/Redis/MongoDB endpoints exposed to the internet should be inventoried and removed from public exposure (PCPJack's scan list). MITRE T1195.002 (Supply Chain Compromise), T1552.001 (Credentials in Files), T1041 (Exfiltration over C2 Channel).

This is the week's defining chain. After the worm framework was open-sourced on 2026-05-12, the window saw it move from a single operator's tool to commodity capability, escalating almost daily:

• 2026-05-18 → 19 — First copycat wave: TeamPCP imitators deploy Phantom Bot plus SSH/cloud stealers, the Checkmarx Jenkins plugin is re-trojanised, and a rival "PCPJack" worm appears, per Ox Security (daily 2026-05-19). Same window: the Nx Console VS Code extension (2.2M installs) is pushed malicious for an 11-minute window (12:36–12:47 UTC, 2026-05-18) via stolen publisher credentials, and all 53 tags of actions-cool/issues-helper are moved to an imposter commit reading /proc/PID/mem of the Runner.Worker (daily 2026-05-20).
• 2026-05-21 — Escalation to platform scale: GitHub itself is named in a breach claim, Microsoft's official durabletask PyPI package is weaponised (propagating via AWS SSM and kubectl exec), and Grafana confirms a missed-token-rotation root cause (The Hacker News; daily 2026-05-21).
• 2026-05-22 — Unit 42 and StepSecurity publish concurrent analyses establishing that SLSA Build Level 3 provenance attestation is invalidated as an integrity gate for these waves — the malicious build step runs inside the legitimately-attested pipeline (Unit 42; daily 2026-05-22).
• 2026-05-23 (disclosure; event 2026-05-18) — SafeDep and OX Security disclose the Megalodon sub-campaign, which mass-poisoned 5,561 GitHub repositories in a ~6-hour window on 18 May using forged CI-bot identities and templated commit messages, harvesting cloud credentials and OIDC tokens (SafeDep; daily 2026-05-23). A further Packagist/Laravel-Lang compromise is reported the same day (daily 2026-05-24).

Two in-window synthesis documents consolidate the picture. The Cloud Security Alliance research note (2026-05-22) frames the whole event as a two-wave attack: Wave 1 (Mini Shai-Hulud, 29 Apr – 12 May) hijacked TanStack's GitHub Actions runner via a pull_request_target trigger plus Actions cache poisoning, extracted a live OIDC token from runner process memory via /proc/PID/mem, obtained a Sigstore signing certificate from Fulcio, and produced SLSA BL3 provenance attestations for 404 malicious package versions across 172 packages (CVE-2026-45321, CVSS 9.6) — the first publicly-documented hijack of trusted build pipelines to generate attestation-bearing malicious artefacts. Wave 2 (Megalodon, from 18 May) pushed 5,718 commits to 5,561 repos in under six hours, harvesting AWS IAM, GCP/Azure IMDS, SSH, Docker auth, .npmrc, .netrc, Kubernetes configs, Vault tokens and Terraform state. Separately, GitHub's official post-incident blog (2026-05-20) confirmed an employee device was compromised via the poisoned Nx Console extension (GHSA-c9j4-9m59-847w) and ~3,800 GitHub-internal repositories were exfiltrated, with no customer-data impact found as of publication and a fuller report still outstanding.

Defender takeaways: set permissions: id-token: none on workflows that do not need OIDC; disable or isolate pull_request_target for fork PRs (permissions: contents: read); treat Git commit author/committer fields as unverified free text (use contributor allow-lists / push-rule bypass-actor audit events to catch Megalodon-style forged identities); audit Sigstore Rekor for unexpected signing events from your own pipeline identity; and do not accept SLSA BL3 attestation alone as a clean-package signal.

The TeamPCP / Mini Shai-Hulud story spans every working day of 2026-W20 and the daily briefs add a piece each day. Tuesday 2026-05-12: an attacker briefly published what appears to be the complete Shai-Hulud framework source (TypeScript / Bun) to a public GitHub repository attributed to TeamPCP, taken down within hours but mirrored widely; the public source disclosure inverts the threat model — every IDE, EDR, and PR-review vendor now has access to the same artefact the operator was using but defenders must assume new variants will appear with one to two days' lead-time on signatures (Datadog Security Labs static analysis, 2026-05-13; daily 2026-05-15 UPDATE). Wednesday 2026-05-13: Wave 4 hits — 170+ packages / 400+ malicious versions compromised per daily-brief tracking across @tanstack (including react-router, ~12M weekly downloads), @uipath, @mistralai, @opensearch-project, and @guardrails-ai; the Wiz writeup confirms the same TeamPCP / UNC6780 / PCPJack attribution as prior waves (Wiz Blog, 2026-05-11; daily 2026-05-13 UPDATE). Friday 2026-05-15: OpenAI named as a victim; the company enforces code-signing certificate rotation across all macOS apps as remediation (daily 2026-05-15 UPDATE).

What W1 horizon research surfaced that the dailies could not yet see: Datadog's static analysis of the leaked source reveals two new capability classes that change the defender posture. First, IDE persistence via hook entries in .claude/settings.json (Claude Code) and .vscode/tasks.json — allowing arbitrary command execution on developer-workspace events; this is not a build-time supply-chain primitive but a developer-workstation persistence mechanism that survives npm install cleanup and outlives the malicious-package removal. Second, OIDC token extraction directly from /proc/<pid>/mem on GitHub Actions runners, used to forge Sigstore provenance attestations — meaning malicious packages can be published that are indistinguishable from legitimate ones by provenance verification alone. The W19 weekly already flagged ShinyHunters / WorldLeaks as a long-running operator-family pattern; the TeamPCP / Mini Shai-Hulud progression confirms a parallel ecosystem maturing on the npm registry side, now with publication-provenance forgery in the toolset. The leaked framework source materially elevates the risk of secondary operators applying Shai-Hulud-style techniques against other package registries (PyPI, Cargo, Maven Central) in 2026-W21 (Datadog Security Labs).

The defender pivot is two-fold: (1) for DevOps pipelines, provenance verification is necessary but no longer sufficient — supplement with publisher-pinning, two-factor publish enforcement, and post-install hash-pinning; (2) for developer workstations, treat .claude/settings.json / .vscode/tasks.json / equivalent IDE hook files as security-relevant configuration and add them to file-integrity-monitoring scope. The Datadog filesystem indicators (gh-token-monitor daemon process, claude@users.noreply.github.com commits in unexpected repositories, exfil-repo names matching "Shai-Hulud: Here We Go Again") are the right hunt seeds.

UPDATE (TeamPCP / mini-shai-hulud first covered 2026-05-07; PCPJack worm covered 2026-05-10; this is a distinct new artefact in the same actor ecosystem): On 2026-05-09–10 (UTC) TeamPCP (UNC6780) published a backdoored build of the Checkmarx Jenkins AST plugin (version 2026.5.09, marketed under the actor's signature naming "Checkmarx-Fully-Hacked-by-TeamPCP") to the Jenkins Marketplace. Any Jenkins instance configured to auto-update the AST plugin during that window pulled the malicious build and executed the SANDCLOCK credential stealer in the runner context (Checkmarx — Ongoing Security Updates, last updated 2026-05-09; The Hacker News, 2026-05-11; SecurityWeek, 2026-05-11).

SANDCLOCK targets every secret reachable from a typical CI/CD pipeline environment: GitHub Personal Access Tokens, AWS / Azure / GCP credentials, Kubernetes service-account tokens, Docker / OCI registry credentials, SSH keys, and Checkmarx One API tokens. Affected pipelines should be treated as full secrets-compromise events: every credential the runner could read must be rotated and any artefact built or deployed in the window audited. Checkmarx's ongoing-security-updates page specifies plugin version 2.0.13-829.vc72453fa_1c16 (published December 2025) as the safe pinned version; a CVE has been issued as CVE-2026-33634 per the Checkmarx advisory. This is the third Checkmarx-product supply-chain compromise by this actor in three months, after the March 2026 KICS Docker image and the April 2026 VS Code extension defacement — the cadence and the actor's naming convention indicate persistent targeting of the Checkmarx product line specifically, not opportunistic distribution-channel abuse.

Mapped to T1195.002 Compromise Software Supply Chain and T1552.001 Credentials In Files. The GTIG AI Threat Tracker (see § 5) attributes SANDCLOCK specifically to TeamPCP and flags the stealer as explicitly designed to harvest LLM API keys in addition to traditional cloud credentials — consistent with the actor's pivot to monetising stolen LLM access. Defender pivot: inventory every Jenkins plugin auto-update enabled across CI/CD estates; constrain runners to short-lived OIDC-federated credentials (no long-lived PATs in runner env) where the platform supports it; audit Checkmarx One API logs for unexpected source IPs since 2026-05-09.

Current state: SentinelLabs documented PCPJack on 2026-05-07 as a worm-class framework that evicts and deletes existing TeamPCP artefacts on compromise (giving the framework its name), then deploys six Python modules harvesting credentials from Docker, Kubernetes, Redis, MongoDB, RayML, and dozens of cloud / SaaS services (AWS, Azure, GCP, GitHub, Slack, HashiCorp Vault, 1Password). Propagation targets are pulled from Common Crawl Parquet files rather than ad-hoc scanning — far broader curated attack surface than typical opportunistic worms. Weaponises five public CVEs simultaneously (CVE-2025-29927 Next.js, CVE-2025-55182 React2Shell, CVE-2026-1357 WPVivid, CVE-2025-9501 W3 Total Cache, CVE-2025-48703 CWP). The TeamPCP → PCPJack succession overlay is the operational specific worth tracking: SentinelLabs explicitly states there is no evidence yet of a direct operator-level connection, while the eviction logic implies operators familiar with TeamPCP's target population. Defenders running self-hosted Next.js, React-server-actions stacks, WordPress with WPVivid Backup or W3 Total Cache, or CentOS Web Panel with internet-reachable FileManager should treat all five CVEs as actively weaponised (SentinelLabs, 2026-05-07 · The Hacker News, 2026-05-07 · SecurityWeek, 2026-05-08 · daily 2026-05-10). The earlier TeamPCP "Mini Shai-Hulud" SAP CAP npm worm (covered 2026-05-06) used Claude Code SessionStart hooks and VSCode tasks for propagation — that thread is separate from PCPJack's CVE-chain propagation but the same operator population is tracked.

SentinelLabs documented PCPJack on 2026-05-07, a worm-class framework that propagates across exposed cloud and web infrastructure by chaining five public CVEs simultaneously: CVE-2025-29927 (Next.js middleware authorisation bypass via crafted header), CVE-2025-55182 ("React2Shell" — Server Actions deserialisation in React/Next.js), CVE-2026-1357 (unauthenticated file upload in WPVivid Backup), CVE-2025-9501 (PHP injection in W3 Total Cache via the mfunc comment processor) and CVE-2025-48703 (shell injection in the CentOS Web Panel FileManager) (SentinelLabs, 2026-05-07 · The Hacker News, 2026-05-07 · SecurityWeek, 2026-05-08). The bootstrap shell script first evicts and deletes existing TeamPCP artefacts from the host (giving the framework its name), then deploys six Python modules covering credential extraction from Docker, Kubernetes, Redis, MongoDB, RayML, and dozens of cloud / SaaS services (AWS, Azure, GCP, GitHub, Slack, HashiCorp Vault, 1Password). A second-stage tooling drops Sliver C2 beacons.

Exfiltration uses Telegram channels with ChaCha20-Poly1305 encryption; propagation target lists are pulled from Common Crawl Parquet files rather than scanned ad-hoc, which gives the campaign a far broader and more curated attack surface than typical opportunistic scanning. Unlike TeamPCP and TeamTNT which monetise via cryptominers, PCPJack drops no miner — SentinelLabs assesses monetisation as credential fraud, spam, access resale, or extortion (SentinelLabs, 2026-05-07). SentinelLabs notes TTP overlap with TeamPCP and frames PCPJack as a possible former affiliate or breakaway operation. Defenders running self-hosted Next.js, React-server-actions stacks, WordPress with WPVivid Backup or W3 Total Cache, or CentOS Web Panel with internet-reachable FileManager should treat all five CVEs as actively weaponised.