Malicious PDF — malware analysis report

Static analysis result for SHA-256 ecb13305331f4a4c…

MALICIOUS

PDF

118.6 KB
MD5: 456689e14ee104500d42aaf9bd34425d SHA-1: 672469cdefe1e52d095d97474d15137380fe5688 SHA-256: ecb13305331f4a4c0b4aed660bcc0f7d51b42677588644ffefe43dd2229fbf3b
166 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript with multiple high-severity heuristic firings, including `PDF_EVAL` and `PDF_JS_LARGE_COMMENT_PADDED_EVAL`. These indicate the script is designed to obfuscate and execute arbitrary code. ClamAV detection as 'Pdf.Exploit.Agent-36086' further confirms its malicious nature. The primary attack vector appears to be exploiting PDF vulnerabilities via JavaScript to download and execute a secondary payload.

Heuristics 7

  • ClamAV: Pdf.Exploit.Agent-36086 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36086
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • Large comment-padded JavaScript eval stager high PDF_JS_LARGE_COMMENT_PADDED_EVAL
    PDF JavaScript contains a very large stream padded with long random-looking block comments around String.fromCharCode and eval. This is an exploit-kit obfuscation shape used to bury a decoder and recovered stage inside noise, not normal PDF form automation.
  • 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.
  • String.fromCharCode low PDF_FROMCHARCODE
    String.fromCharCode found — used to construct payload strings dynamically. Common in benign JavaScript libraries for codepoint manipulation, so this alone is informational; weaponised use is also caught by the dedicated fromCharCode-stage and exploit-shape rules. (matched inside decoded 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0006_000.js
64acd28631572399b31450a601b9a347122739e05dc2bdbcf4c785af5653105e
pdf-javascript-stream PDF /JS object 6 at offset 0x143 626986 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s). Carved artifact contains 42 long base64-like blob(s).
stream_002_off0001d8c9.bin
e6db0d07e178c7be9a34c27256d138052eb0eb59cb2b22194da87ba25fd9d921
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x1D8C9 200 bytes