Malicious PDF — malware analysis report

Static analysis result for SHA-256 37fa3ea9d65c4278…

MALICIOUS

PDF

11.4 KB
MD5: 93c38328dc0d3e73a517d1a579decb5c SHA-1: 269ff3a9585bf59030406bb57875c8dd59907f5f SHA-256: 37fa3ea9d65c4278c7023f4c4077cef23499f9c73b0d6aa57204b434a8f33019
200 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File T1027 Obfuscated Files or Information

This PDF file contains embedded JavaScript, identified by multiple critical heuristics including PDF_JAVASCRIPT, PDF_JS, and CVE_2007_5659. The CVE_2007_5659 heuristic specifically indicates the use of a 'Collab.collectEmailInfo' method with hex-decoded JavaScript, which is then evaluated. The presence of deobfuscated JavaScript files ('legacy_pdfkit_stage_000.js', 'legacy_pdfkit_stage_001.js') suggests a multi-stage attack. The primary intent appears to be the execution of malicious JavaScript, likely to download and execute a secondary payload, as indicated by the ClamAV detection of 'Pdf.Exploit.Agent-36065'.

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)
  • Annotation subject percent-decoding eval stager critical PDF_ANNOT_SUBJECT_MARKER_EVAL_STAGER
    OpenAction JavaScript forces annotation enumeration, reads an annotation /Subject payload with getAnnots(), rewrites marker bytes into percent escapes, decodes it with unescape(), and dispatches it through eval. This is a high-confidence exploit-kit staging pattern. It is intentionally not mapped to CVE-2009-1492 unless getAnnots() itself carries the crafted integer or long argument shape for that vulnerability.
  • ClamAV: Pdf.Exploit.Agent-36065 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36065
  • 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.
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser exited 1. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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
9c67560e8c63b720885d3efc1627b844b86a6ec08e99e5b65a22eae832045756
pdf-javascript-stream PDF /JS object 7 at offset 0x19C 431 bytes
legacy_pdfkit_stage_000.js
9375dc9ba21326f21e6ca5fbffc0783ee8ad92406d5cefdb35610ce7ad65cc53
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x315 11637 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
ba8f85fd3df00beb076792114b90c6cec8285a245e9551a1d67efd2844e3332f
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x315 4706 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).