PDF malware analysis — malicious · f76dbed712bc7f22

MALICIOUS

PDF

8.0 KB

MD5: 38c510dd278ac03ff8e915a0c09e1f7a SHA-1: aebc6dfd905f076bce37f834697c1ff2d11a4178 SHA-256: f76dbed712bc7f220fd6edcaf0b67dba70da8804527467ece687799b40e9ac3b

256 Risk Score

Malware Insights

MITRE ATT&CK

T1059.001 JavaScript/JScript T1204.001 Malicious Link/Object

The PDF file contains obfuscated JavaScript that leverages the CVE-2007-5659 vulnerability, specifically targeting the 'collab.collectEmailInfo' function. This JavaScript dropper is designed to download and execute a second-stage payload. The ML classifier and ClamAV detection strongly indicate malicious intent, and the presence of multiple deobfuscated JavaScript files suggests a complex, multi-stage attack.

Machine Learning

Nyx PDF Classifier malicious score 1.0000

Heuristics 8

Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659

PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (identified after JavaScript deobfuscation)
ClamAV: Pdf.Exploit.Agent-36086 critical CLAMAV_DETECTION

ClamAV detected this file as malware: Pdf.Exploit.Agent-36086
unescape() call high PDF_UNESCAPE

unescape() found — often used to decode shellcode in PDF JS exploits (matched inside decoded stream)
Obfuscated multi-stage PDF JavaScript dropper high PDF_JS_OBFUSCATED_DROPPER

PDF JavaScript shows 3 independent signals of exploit-kit-style multi-stage obfuscation: annot_subject_stage, 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.
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_obj0006_000.js` `f9b4659beaf681d266cfb5046d495e7b144d406eff72e71ecd4d1451ae25ca11`	pdf-javascript-stream	PDF /JS object 6 at offset 0x143	481 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` `e611b7739eb4cb3f95335af79f824eec5f7a3d33b095d44a8b691a9c8982a1f0`	deobfuscated-js	repeated-marker hex decoded JavaScript at offset 0x1ACE	1707 bytes
Detection ClamAV: No threats found Obfuscation or payload: likely Carved artifact contains 1 eval/decoder/string-building token(s).
`legacy_pdfkit_stage_001.js` `556b3e0abd0a232787db88e193c651961d55f865f79f5ffec123af4e18b2f1b3`	deobfuscated-js	annotation-subject callee-key decoded JavaScript at offset 0x329	5008 bytes
Detection ClamAV: No threats found Obfuscation or payload: likely Carved artifact contains 5 eval/decoder/string-building token(s).
`deobfuscated.js` `dae8b774ba0b0d40439fe5865a035e4f364276bcf2de81d870a96885361791a1`	deobfuscated-js	PDF JavaScript deobfuscation pass	24653 bytes
Detection ClamAV: No threats found Obfuscation or payload: likely Carved artifact contains 4 eval/decoder/string-building token(s). Carved artifact contains 2 long base64-like blob(s).

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