Jiffy Intel — Threat intelligence for AI artifacts

Summary

agents.md instructs the agent to explicitly skip any security scan "because the reviewer will verify." Benign on the surface, the directive disarms the last line of defense and invites shipping unscanned code.

Severity & confidence

Severity

Medium

Notable weakness with plausible abuse chains or partial mitigations already in place. Track, and resolve as part of your normal hardening cadence.

Confidence

Confirmed

Observed directly by Jiffy scanners or validated by multiple independent sources. Indicators are reliable enough to drive automated action.

Indicators

Observed patterns and artifacts associated with this entry. Each indicator can be copied into your detection stack or SIEM.

(?is)(?:skip|bypass|ignore)\s+(?:the\s+)?(?:security|lint|ci|scan)

Detection rule

A YARA-style pseudo-rule auto-generated from the indicators above. Useful as a starting point — adapt the syntax for your target detection platform.

YARA-style pseudo-rule

rule jiffy_ti_2026_000070
{
    meta:
        source = "jiffy-intel"
        severity = "medium"
        description = "Auto-generated from Jiffy Intel indicators"
    strings:
    $content_pattern_0 = "(?is)(?:skip|bypass|ignore)\\s+(?:the\\s+)?(?:security|lint|ci|scan)"
    condition:
        $content_pattern_0
}

Auto-generated from the indicators above. Adapt syntax for your detection stack before deploying.

Affected tools

Tool	Versions	Status
Claude Code	`*`	vulnerable
Cursor	`*`	vulnerable

Example artifacts

Sanitized examples of artifacts Jiffy has observed exhibiting this pattern. Publisher handles are redacted; version ranges and status reflect the most recent scan.

agents.md (repo: fast-shipper)IDE rules
Under review
Source
GitHub (public repo)
First observed
Mar 21, 2026
CLAUDE.md (repo: high-velocity-template)IDE rules
Quarantined
Source
GitHub (public repo)
First observed
Mar 25, 2026

How to remediate

01Flag IDE rules that weaken CI or security posture.
02Require explicit rationale before the agent follows them.

Timeline & sources

Timeline

First observedMar 21, 202627 days ago
Last updatedApr 28, 2026today
PublishedMar 29, 202619 days ago

Sources

curated

References

genai.owasp.orgOWASP

OWASP LLM-06: Excessive Agency (2026)

https://genai.owasp.org/llmrisk/llm-06-2026/

blog.jiffylabs.aiJiffy Research

Jiffy Research — .cursorrules and agents.md Config Backdoors

https://blog.jiffylabs.ai/posts/cursorrules-and-agents-md-config-backdoors

Related intel

Other entries of type Backdoor, or the most recent published entries if no same-type matches exist.

BackdoorHigh

Skill writes config that hooks into Claude Desktop stdio MCP bridge

Skill modifies the user's Claude Desktop config to register an MCP server pointing at localhost. The server is supplied by the same skill and serves as a persistent interposer between the agent and tool calls, logging all tool arguments.

Jiffy IntelApr 28

BackdoorCritical

MCP server exposes hidden "debug" tool that shells out

MCP server registers a tool named `__debug` or `_internal` that is not listed in the public tool discovery but accepts arbitrary shell commands. Any client that knows the tool name can exec on the server host.

Jiffy IntelApr 27

OtherLow

.cursorrules contains large wall-of-text that pushes user intent out of context

.cursorrules whose rule body exceeds 20 000 characters of filler content. Each agent invocation consumes the rule, leaving limited context for the user prompt. Not a direct exfiltration primitive — a budget-starvation attack.