Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5c54828e1767b4a…

MALICIOUS

PDF

12.3 KB
MD5: 66af1f062536cd6964b563a68bbe0861 SHA-1: 693b2f6b7049d4c984c381d7f8201f872a68f0ee SHA-256: b5c54828e1767b4a6d48556aca51ec2cab82bc3e261546c231ca34e7b9df68d8
186 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript/JScript T1204.002 Malicious File T1059.003 Windows Command Shell

The PDF file contains embedded JavaScript, triggered by the CVE-2007-5659 vulnerability (Collab.collectEmailInfo). This JavaScript acts as a stager, decoding and executing a larger payload. The ClamAV heuristic also flags this as Pdf.Exploit.Agent-36063, indicating a known exploit. The primary attack vector is the exploitation of the PDF reader to run arbitrary code.

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
0f514221fe6b14dbf9cdf401860eb99f10f14acfb076d36acadbc8e03571f118
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5280 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
deobfuscated.js
b8d1dba764679bda2aa5c8420e17d952ef48b2295c5de0a0882c3f812aeaa442
deobfuscated-js PDF JavaScript deobfuscation pass 80735 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).