Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b4fbeafa7be1126…

MALICIOUS

PDF

9.6 KB
MD5: 111cce49a0119849ca57315ddc34413d SHA-1: 17824ecdc38aee28621b372e1b9bfcfbed2e495d SHA-256: 3b4fbeafa7be1126fd87999793c448d952180c63de90a35ec82e1a94e031f378
126 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript/JScript T1204.002 Malicious File

The PDF sample contains embedded JavaScript, triggered by the 'collab.collectEmailInfo' function, which is known to be vulnerable (CVE-2007-5659). The embedded JavaScript is heavily obfuscated and appears to be a stager. The primary mechanism involves exploiting a PDF reader vulnerability to execute this script, which then likely downloads and executes a second-stage payload. The deobfuscated JavaScript is substantial, indicating complex malicious activity.

Heuristics 6

  • 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)
  • 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
b9a85ee399db318b3ad68d0755effe289a645a7404fad2094712c8a3fd042920
pdf-javascript-stream PDF /JS object 7 at offset 0x19B 244 bytes
annotation_subject_callee_hex_stage_000.js
9f6d821f1fc74816eb5339cce30bcc76b92a21d5bafb5b0dd79cbf62914bfad0
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5217 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
deobfuscated.js
69cddbd60616806eda06070f5e22d00d2ecf3b04549291837065fee697508c3f
deobfuscated-js PDF JavaScript deobfuscation pass 44491 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).