Malicious PDF — malware analysis report

Static analysis result for SHA-256 da3d3e18009af513…

MALICIOUS

PDF

11.9 KB
MD5: 8c920db16622fa5025e32117f1e93021 SHA-1: baa9122060202ff4005c32f9ddbbc5c2a65ccece SHA-256: da3d3e18009af51344c45b589562d7bc9bc0e9211dbfb1b3e64da73f76efd8a5
200 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link or Macro: Malicious Link

The PDF file contains embedded JavaScript, triggered by the 'Collab.collectEmailInfo' method which is associated with CVE-2007-5659. This JavaScript is further obfuscated and appears to be a stager, as indicated by the 'eval stager' heuristic and the presence of deobfuscated JavaScript files. The ClamAV detection 'Pdf.Exploit.Agent-36065' confirms the malicious nature. The primary function is likely to download and execute a secondary payload.

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
59ebaa1974472f7e9698aa747a75657bd0e0c2f64c95d8b8b01b1fe6e73fe6d8
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x315 12184 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
23e81fdef718c1d66f598cec4f717e174c3545748f42905257f01ad9a10f0d3f
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x315 4987 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).