Malicious PDF — malware analysis report

Static analysis result for SHA-256 f10339a4d0ecac25…

MALICIOUS

PDF

11.5 KB
MD5: d7f1b4204c1babccbd6eeab566be9079 SHA-1: 78b5d3d317b054f4e4ec7727d922e4aefc68b6f0 SHA-256: f10339a4d0ecac25832ddd7fd443d63b17773e49e6578471e1d8ab013a2e7b5d
186 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, specifically identified as a stager for CVE-2007-5659, which is a critical vulnerability related to the `Collab.collectEmailInfo` function. The heuristic firings indicate that the PDF launcher uses this function to extract and decode a JavaScript payload, which is then evaluated. This process is designed to execute arbitrary code, likely to download and run a second-stage payload. The ClamAV detection further confirms the malicious nature of the file.

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
6ac73c09a1d46e593f0b0523d41800e259ee7036bc37cb8ae93196107df7bebf
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 4915 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
8f9ba1b0f062f4f5b118b880ec811a01385f20e10d59ffd1eeb80c66537f9da6
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2D6 11718 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
103ae4513d695fad3ccd971029e02e132521720c3b149c3bfc2815bdff66ac9d
deobfuscated-js PDF JavaScript deobfuscation pass 79463 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).