Malicious PDF — malware analysis report

Static analysis result for SHA-256 eb2399e88c9e8ebe…

MALICIOUS

PDF

8.0 KB
MD5: e97deede215c59ab60964a304bd1159f SHA-1: d4bf6884363e9edcb678b029357079e70ff0ebc2 SHA-256: eb2399e88c9e8ebe185fbf467c773e2a51adbca14c4297d6414437a42a5e05c0
194 Risk Score

Malware Insights

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

The PDF document contains obfuscated JavaScript, identified as a multi-stage dropper. The critical heuristic CVE_2007_5659 indicates exploitation of a known vulnerability in PDF viewers. The JavaScript is heavily obfuscated, making its exact payload difficult to determine, but its dropper nature suggests it is designed to download and execute further malicious content. The presence of multiple deobfuscated JavaScript files further supports this multi-stage execution.

Heuristics 8

  • 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)
  • ClamAV: Pdf.Exploit.Agent-35916 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-35916
  • Obfuscated multi-stage PDF JavaScript dropper high PDF_JS_OBFUSCATED_DROPPER
    PDF JavaScript shows 5 independent signals of exploit-kit-style multi-stage obfuscation: annot_subject_stage, hex_codec_loop, hex_dashed_payload, incremental_eval_build, repeated_pluginschk. This is strongly consistent with pre-2011 Adobe Reader PDF droppers — OpenAction JS reads encoded data from annotation subjects, decodes it through one or more hex / base-N loops, and invokes eval indirectly (method name built one character at a time). The actual CVE is hidden in the final decoded layer and is not visible via static analysis.
  • 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)
  • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0005_000.js
6c41320119e160dc719997b9a2efb3600ea9d7e9d7e44b4dc2125762dc9f365f
pdf-javascript-stream PDF /JS object 5 at offset 0x148 505 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).
legacy_pdfkit_stage_000.js
3f167b4a42b2648a4f41e281aa26ca5e89c47e0cbc34241ed0fc4350174f6844
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x1AAF 1773 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
legacy_pdfkit_stage_001.js
7c0ecca5bb364e95eb8ec9a0e9d6f9db1bbd75ac209f8d83c7e272189a4a32ed
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x352 4891 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 4 eval/decoder/string-building token(s).
deobfuscated.js
85556bc3e6b5ad4256287adb44a037b2ccfbfdf0ee6e1017b92c844925cc6b42
deobfuscated-js PDF JavaScript deobfuscation pass 25729 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 7 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).