Malicious PDF — malware analysis report

Static analysis result for SHA-256 158b47727435e863…

MALICIOUS

PDF

81.8 KB Created: 2021-09-18 03:27:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: cdeba705939eeb9f0fb0661500821d01 SHA-1: 122fcb542590c79a95fd72f6cde8a9b5a108f1d2 SHA-256: 158b47727435e8637ad121db67cf0d7a26ce5b10ce38aabf8ca903ca34ed4e56
124 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple embedded URLs, many hosted on compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The ML classifier strongly flagged this PDF as malicious. While no scripts were explicitly extracted, the presence of numerous external links and the 'urgency lure' heuristic indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

Heuristics 7

  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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 https://allytemp.ru/uplcv?utm_term=transfer+photos+to+phone PDF link annotation
    • http://slhospital.com/upload/fckeditor/file/71013013091.pdfIn PDF document text
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/161351a235a66b---dolazil.pdfIn PDF document text
    • https://hankilfood.com/userfiles/file/20210902140700.pdfIn PDF document text
    • http://sh-ruiyangcpa.com/userfiles/file/2021-9///202192652512638.pdfIn PDF document text
    • http://imapbook.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/17332288686.pdfIn PDF document text
    • http://letnipohar.cz/upload/file/jujemaku.pdfIn PDF document text
    • https://www.sistemkabin.com/ckfinder/userfiles/files/gigifogawefetaf.pdfIn PDF document text
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/3a63042fddd0713715cfc29f638f1119/torupijuzemixutesero.pdfIn PDF document text
    • http://htwy.com/upload/file/sebila.pdfIn PDF document text
    • http://www.barbazan-debat.fr/ckfinder/userfiles/files/55606536580.pdfIn PDF document text
    • https://tekstilkentrehber.com/upload/ckfinder/files/pajil.pdfIn PDF document text
    • http://theclelandgroup.com/img/upload/file/79490933292.pdfIn PDF document text
    • http://alimentosldm.com/userfiles/file/pinobemiworusakewofigosap.pdfIn PDF document text
    • https://beautifullifeuk.com/wp-content/plugins/super-forms/uploads/php/files/2c2c2ceaeeb85bd20170bd42e05d4384/sewobegezok.pdfIn PDF document text
    • http://mamolenasnc.it/userfiles/files/47056795269.pdfIn PDF document text
    • http://ieltsadd.ir/cache/fck_files/file/dimivigewi.pdfIn PDF document text
    • http://patrick-jardinage.fr/ckfinder/userfiles/files/45579991495.pdfIn PDF document text
    • https://www.karelo.com/uploads/File/54428767319.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/531b6dfcbc6ab39ed2a0f55403590247/tovekidudazodewifub.pdfIn PDF document text
    • https://karolinanowak.com/userfiles/file/tapevikifinifutup.pdfIn PDF document text
    • http://ninda.vn/userfiles/files/baxuzutozikomulovu.pdfIn PDF document text
    • http://bubb.cn/up_file/file/86190818830.pdfIn PDF document text
    • http://logicparcel.net/uploadsEditorfile/jawabepo.pdfIn PDF document text
    • http://es-umzuege-transporte.de/wp-content/plugins/super-forms/uploads/php/files/b375c98fae3dcec15757423aacb00934/semubonasojesevo.pdfIn PDF document text
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/1614507509252d---27137735375.pdfIn PDF document text
    • http://dietgame.net/admin/fckeditor/data/file/20210905201126.pdfIn PDF document text
    • https://standsimulator.com/ckfinder/userfiles/files/41113876275.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dddd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDDD 10280 bytes
SHA-256: 0cefbcb129eda42694e8b6cc4557d403986bb89e152383e98912e7e02b09de59
font_01_sfnt_off0000f4f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4F6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010d08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D08 17220 bytes
SHA-256: 50fb99c39fa1904d089a4f04de618b9832ed2d9ea688b2fffaa03599b555e83c