Malicious PDF — malware analysis report

Static analysis result for SHA-256 fec5efdc7141f6ba…

MALICIOUS

PDF

9.4 KB
MD5: 6885dfe8f16b72a0d6049b3ab4b7cbd1 SHA-1: f8ad77427dda34eb0bf461caef351edb853218aa SHA-256: fec5efdc7141f6ba5cae8a50a56d7599f34e5c4de07e7dad630bb041d6cac617
126 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, triggered by the CVE-2007-5659 vulnerability via the `collab.collectEmailInfo` function. This JavaScript is heavily obfuscated but appears to be a stager designed to download and execute a second-stage payload. The presence of multiple JavaScript streams and the specific exploit technique point to a malicious PDF designed for exploitation.

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
dc37160715dd481d0bf49e7af5079aad16ed0e66896c1ae05ca27000b3e4454e
pdf-javascript-stream PDF /JS object 7 at offset 0x19B 259 bytes
annotation_subject_callee_hex_stage_000.js
b16f9e8225173047ad6502da70236d4a61ab4178c82819943b6b5cce11c9c8a8
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5075 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
deobfuscated.js
f388219a298f2edc5a55a782f8c25a202f25a75a405d8071101a8bffb96a31ce
deobfuscated-js PDF JavaScript deobfuscation pass 46279 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).