Malicious PDF — malware analysis report

Static analysis result for SHA-256 4970c3e2e2f009b9…

MALICIOUS

PDF

12.0 KB
MD5: 55cd3ca1dacd1d912892a9f02079baaa SHA-1: 59b417a626784286ae0e63249cf3d1eaeec79963 SHA-256: 4970c3e2e2f009b9b5656abd654d7547750a437bc925aedde0ad40e732d6b603
186 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link

The PDF file contains embedded JavaScript, specifically leveraging the CVE-2007-5659 vulnerability through the `Collab.collectEmailInfo` method. This JavaScript is heavily obfuscated and appears to be a stager, indicated by the heuristic `PDF_ANNOT_SUBJECT_CALLEE_HEX_STAGER`. The deobfuscated JavaScript is substantial, suggesting it performs complex actions such as downloading and executing further payloads. The presence of multiple JavaScript streams and the ClamAV detection further support its malicious nature.

Heuristics 7

  • 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-36063 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36063
  • Annotation subject callee-key hex JavaScript stager high PDF_ANNOT_SUBJECT_CALLEE_HEX_STAGER
    PDF JavaScript uses syncAnnotScan()/getAnnots() to read an indirect annotation /Subject stream, percent-decodes it through marker replacement, then uses a callee.toString()-derived key to decode and eval the final exploit stage.
  • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
eb39e2de4dbbc100de6d3e30aa43ff78fa075618862ba1ebba5151ea3a3b848d
pdf-javascript-stream PDF /JS object 7 at offset 0x19D 273 bytes
annotation_subject_callee_hex_stage_000.js
fd8ab585c40771b7c2b586a5f66ddbb516af56ca9a2503f447a83eb24fc3566c
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5112 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
deobfuscated.js
b40dae511b2d56155abfe0b98abcd7df54fedf74f7f89a7082c1b778fafbabec
deobfuscated-js PDF JavaScript deobfuscation pass 78996 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).