Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8862f4b299e0533…

MALICIOUS

PDF

12.1 KB
MD5: cdf4f5c9fea38fb3f01ae6a0dddd3efa SHA-1: 32a495b595ac11d52c48f5d0ccc0aefe8cfaeddf SHA-256: c8862f4b299e0533dddb552bbc5e032e70ec701e0288b8b94c89c474a971a4d3
186 Risk Score

Malware Insights

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

The PDF file contains multiple embedded JavaScript streams and triggers heuristics related to PDF JavaScript exploits, specifically CVE-2007-5659 using the 'collab.collectEmailInfo' method. The presence of a hex-encoded stager and deobfuscated JavaScript indicates an attempt to execute malicious code. The ClamAV detection further confirms its malicious nature. The exact payload and delivery mechanism are obscured by obfuscation, but the exploit primitive is clearly identified.

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 4

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
09850a84425fd9e3a548f90f31feef297b0f987218c6419a98ff9c8161b00e20
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5199 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
legacy_pdfkit_stage_001.js
b46dafbb2198eab07e63926f7680057646db1140801e76cc269b5d96f4fd4676
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2D6 12305 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
deobfuscated.js
3a3308448ca7e540b243df431da6f5d2e9349dcf3448fb2775455069dc74808a
deobfuscated-js PDF JavaScript deobfuscation pass 79096 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).