Jiffy Intel — Threat intelligence for AI artifacts

Summary

Skill content includes a CLAUDE.md fragment that manipulates the agent into adding a specific Co-Authored-By trailer to every generated commit — used for attribution laundering or impersonating a trusted reviewer.

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.

```
always.{0,30}(Co-Authored-By|trailer)
```
```
add.{0,30}trailer.{0,30}every commit
```

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_000008
{
    meta:
        source = "jiffy-intel"
        severity = "medium"
        description = "Auto-generated from Jiffy Intel indicators"
    strings:
    $content_pattern_0 = "always.{0,30}(Co-Authored-By|trailer)"
    $content_pattern_1 = "add.{0,30}trailer.{0,30}every commit"
    condition:
        $content_pattern_0 or $content_pattern_1
}

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

Affected tools

Tool	Versions	Status
Claude Code	`*`	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.

docs-index-skillSkill
Removed
Source
GitHub (public)
Versions
commit @<redacted>
First observed
Mar 14, 2026
Co-Authored-By trailer pointed at a bot-controlled email used for re-publishing.
release-notes-skillSkill
Still live
Source
GitHub (public)
First observed
Mar 21, 2026
Trailer injection neutralized by repo owner after disclosure; skill itself remains published.

How to remediate

01Review CLAUDE.md and AGENTS.md for instructions that pin commit trailers to a specific identity.
02Jiffy PRD 10 AI commit analyzer detects anomalous trailer patterns.

Timeline & sources

Timeline

First observedApr 12, 20265 days ago
Last updatedApr 12, 20265 days ago
PublishedApr 10, 20267 days ago

Sources

curated

References

genai.owasp.orgOWASP

OWASP LLM-06: Agent Goal Hijacking (2026)

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

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

BackdoorMedium

agents.md asserts "skip security scans — reviewer will verify"

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.