Malicious PDF — malware analysis report

Static analysis result for SHA-256 88c85465307ce800…

MALICIOUS

PDF

118.7 KB
MD5: 57b6911a8fd8cbf325c0cfc5a90b5116 SHA-1: d17151d7ebcf38cb2471bcc15e94913d331006b8 SHA-256: 88c85465307ce8005334f63d95f2fa65c3b6b2d64b0801de75ea2512199e8f86
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell

The PDF file contains multiple heuristic firings indicating embedded and obfuscated JavaScript, including a large comment-padded eval stager. ClamAV detected this file as 'Pdf.Exploit.Agent-36086'. The embedded JavaScript is likely responsible for downloading and executing a second-stage payload, which is a common technique for malware delivery.

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
cc30700ed7a9c56026525e897e728047ea5bbb01d93e808dc4cddb550e4f9435
pdf-javascript-stream PDF /JS object 6 at offset 0x143 627689 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_001_off0001d733.bin
1927b456dcee20874ff5c9052825cfe21d10d53a559adb3bad1e205e1db00d13
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x1D733 300 bytes