Malicious PDF — malware analysis report

Static analysis result for SHA-256 4645607d90a72c35…

MALICIOUS

PDF

75.3 KB Created: 2021-07-12 17:28:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 18e1af8438834d7233f29a8338159482 SHA-1: 5d44cf51954dc35b6683eaed83347c9f33514dd6 SHA-256: 4645607d90a72c35da1f91f296ffe780b2b3c316d1bada99ca2e8241835208e9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple distinct hosts, some of which are associated with compromised CMS uploads. The document body is heavily obfuscated and unreadable, suggesting it is not intended for user consumption but rather to host these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://sarljarry.fr/userfiles/file/wunotukelidagelagegapix.pdf
    • http://bjhtdszdh.com/v15/Upload/file/2021511322413076.pdf
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c1ee514113---24638473530.pdf
    • http://suankaew.net/upload/userfile/files/77135314961.pdf
    • https://paron-rebondir.com/uploads/files/doxowegafipu.pdf
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a31ecd842fa---83865291186.pdf
    • https://bwawarszawa.pl/upload/file/zugugigoxuvebemaborid.pdf
    • http://yeosingol.com/FileData/ckfinder/files/20210708_36EB996EEE83AAC7.pdf
    • http://midiabyz.com/wp-content/plugins/super-forms/uploads/php/files/99e766e503fb8bd930effdd20ff3431d/delapozub.pdf
    • https://apinero.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b6f2874b03---gilubukis.pdf
    • https://roc.mn/uploads/files/mopisimunikologexufapapew.pdf
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e7d9816cc2f---97857219555.pdf
    • http://shinies.ru/img/lib/file/77873012921.pdf
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ca811c7528---96989505265.pdf
    • https://amrapalispot.com/userfiles/file/zudizomesefupojatajos.pdf
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160e069a38afb7---68914756564.pdf
    • https://study4student.com/cache/fck_files/file/kozevenavewabupuzavefe.pdf
    • http://italiancousins.net/clients/5/54/54f3d33123424807706abe9154268524/File/52885424006.pdf
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e03a85530ed---nujaromasalalojerupeli.pdf
    • http://hillcountryawningsandsunscreens.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607462c1991d1---49918778127.pdf
    • https://joefairless.com/wp-content/plugins/super-forms/uploads/php/files/d89151c2633edf8ed3b004dfdeff04b5/dowakonenatipadobogogu.pdf
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/e72b8c7c8ed8d6e169dc0dfc97a41cc6/15935244661.pdf
    • http://moreit.ch/productinfo/file/98480447285.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=here+i+am+to+worship+bass+chords
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c3bd.bin
16404022e340d8a48d09f002f2188c5804e5cc2890d6d7829ae05ffcd4d3bcde
pdf-font-stream PDF embedded font (sfnt) at offset 0xC3BD 16624 bytes
font_01_sfnt_off0000eece.bin
6e9edb805fbf316098bfec1f666eb1d1a624776955b0e3001f74070acfc26156
pdf-font-stream PDF embedded font (sfnt) at offset 0xEECE 10844 bytes
font_02_sfnt_off000107b0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x107B0 16792 bytes