PDF malware analysis — malicious · d3612d127735a68f

MALICIOUS

PDF

35.2 KB

MD5: 262125128a80bc3e8828d5036a99f21f SHA-1: 52bf221f4f1fc7f874d5311b8d4adfd281a4145c SHA-256: d3612d127735a68fac565bf1522a56299a549bfcda481beaf562c096995241e8

174 Risk Score

Malware Insights

MITRE ATT&CK

T1059.001 JavaScript T1204.002 Malicious JavaScript

This PDF file contains obfuscated JavaScript, indicated by the 'PDF_JS_OBFUSCATED_DROPPER' heuristic. The JavaScript is designed to be a multi-stage dropper, likely exploiting a CVE-related vulnerability in Adobe Reader's 3D content parsing (indicated by 'PDF_U3D_CVE_RELATED'). The primary function appears to be downloading and executing a second-stage payload from external sources, as suggested by the embedded JavaScript streams and the ClamAV detection name 'Pdf.Exploit.Agent-35902'.

Heuristics 8

U3D/3D content in PDF — Adobe Reader 3D parser CVE-family indicator high CVE related PDF_U3D_CVE_RELATED

PDF contains U3D (Universal 3D) or 3D annotation content — CVE-2011-2462 and CVE-2009-3953 are critical vulnerabilities in Adobe Reader's U3D processing that allow arbitrary code execution. U3D content in PDFs is extremely rare in normal documents.
ClamAV: Pdf.Exploit.Agent-35902 critical CLAMAV_DETECTION

ClamAV detected this file as malware: Pdf.Exploit.Agent-35902
Obfuscated multi-stage PDF JavaScript dropper high PDF_JS_OBFUSCATED_DROPPER

PDF JavaScript shows 5 independent signals of exploit-kit-style multi-stage obfuscation: annot_subject_stage, hex_codec_loop, hex_dashed_payload, incremental_eval_build, repeated_pluginschk. This is strongly consistent with pre-2011 Adobe Reader PDF droppers — OpenAction JS reads encoded data from annotation subjects, decodes it through one or more hex / base-N loops, and invokes eval indirectly (method name built one character at a time). The actual CVE is hidden in the final decoded layer and is not visible via static analysis.
JavaScript action low PDF_JAVASCRIPT

PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
Embedded JS stream low PDF_JS

PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
String.fromCharCode low PDF_FROMCHARCODE

String.fromCharCode found — used to construct payload strings dynamically. Common in benign JavaScript libraries for codepoint manipulation, so this alone is informational; weaponised use is also caught by the dedicated fromCharCode-stage and exploit-shape rules. (matched inside decoded stream)
syncAnnotScan annotation-staging primitive low PDF_FOXIT_SYNCANNOTSCAN

PDF JavaScript calls syncAnnotScan() — a no-op annotation-enumeration primitive used by exploit-kit JavaScript to stage payload reads from annotation /Subject fields before eval(). Not a vulnerable sink itself; rarely seen in legitimate PDFs. (matched in decompressed stream)
Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE

One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 4

Files carved from inside the sample during analysis.

Filename	Kind	Source	Size
`javascript_obj0005_000.js` `3cf6a22459cda11e607fc9e0dc0c88d01a8425e26488ff87df38d855ceb4dccf`	pdf-javascript-stream	PDF /JS object 5 at offset 0x14F	465 bytes
Detection ClamAV: No threats found Obfuscation or payload: likely Carved artifact contains 1 eval/decoder/string-building token(s).
`legacy_pdfkit_stage_000.js` `1d84fe44a056d052112bc5855c2703424f9eb40958452e8952d3acb31a674106`	deobfuscated-js	repeated-marker hex decoded JavaScript at offset 0x1BD3	1721 bytes
Detection ClamAV: No threats found Obfuscation or payload: likely Carved artifact contains 1 eval/decoder/string-building token(s).
`deobfuscated.js` `a88edcf22449d776dd19e1bcfdc142bd7ac6aea5c1fbb49fafeacdf9bc5528b7`	deobfuscated-js	PDF JavaScript deobfuscation pass	179347 bytes
Detection ClamAV: No threats found Obfuscation or payload: likely Carved artifact contains 5 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
`u3d_00_off000020aa.bin` `fb27c6f6ffe2b08a88f79f344ef3cb4f85460ac81a062194b6fd84ab6e48b628`	pdf-3d-stream	PDF U3D 3D stream at offset 0x20AA	28021 bytes
Detection ClamAV: No threats found Obfuscation or payload: likely Carved artifact entropy is 7.79, consistent with packed or encrypted content.

Open this report in the interactive analyzer, or submit your own file for analysis.