Malicious PDF — malware analysis report

Static analysis result for SHA-256 e21a865413ce7669…

MALICIOUS

PDF

9.8 KB
MD5: 0146b85c795b658aadba53633593199e SHA-1: 527df6080a1efd022ca491587e388e7746b37449 SHA-256: e21a865413ce7669d3b19432236317aef5d165283de3447f4758df86e2641fc6
126 Risk Score

Malware Insights

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

The PDF document contains embedded JavaScript, triggered by the CVE-2007-5659 vulnerability via the Collab.collectEmailInfo function. This JavaScript is heavily obfuscated and hex-encoded, acting as a stager. The deobfuscated script is substantial, indicating it's designed to download and execute further malicious content. The primary attack vector is the exploitation of a known PDF vulnerability.

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
edb1c2d24ef865baf6229a8e6a63474f7cbe56e08f6db2895bb2db7e027a3fa2
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5335 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
deobfuscated.js
1b3a859bca615053abcaf8c56c962984a7baab11ec3efb03db54ae5e6c9a5e48
deobfuscated-js PDF JavaScript deobfuscation pass 46382 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).