Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc4a90efb9cbad18…

MALICIOUS

PDF

11.8 KB
MD5: eceedbfe4c11824c9516dd0ea13380b0 SHA-1: dc85d7fcf2be62586a12426becda323b661bf431 SHA-256: fc4a90efb9cbad18f9d778fdd4315869a163274b91440c9ac24047af43115441
186 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File

The PDF file contains embedded JavaScript, triggered by the CVE-2007-5659 vulnerability (Collab.collectEmailInfo). The heuristics indicate that this JavaScript acts as a stager, decoding and executing further malicious code. The ClamAV detection of 'Pdf.Exploit.Agent-36063' further confirms its malicious nature. The primary attack vector is the exploitation of a PDF reader vulnerability 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 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
22cd0ce75b30b8be9e19397bc74be17235f9030180c86caab09b4a5b6deb0725
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 4988 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
947e02477c21e4d36e20bc92415559ed3e65a5f5afe91d0af5305517f3e4e6ac
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2D6 11949 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
f217c130489e08a7a39e6e676dfac0baa17275f32cec9b9c26e72b55f5556077
deobfuscated-js PDF JavaScript deobfuscation pass 72076 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).