Malicious PDF — malware analysis report

Static analysis result for SHA-256 543e7856cf3f4ce7…

MALICIOUS

PDF

89.4 KB Created: 2021-07-05 23:18:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 925d35e7019ab7f5948fc305510831eb SHA-1: d43ca77511f51e0c9b6dc9a58a823ae696dbda6b SHA-256: 543e7856cf3f4ce71245dc9b88085799e4d076283afa3bd6b3c3a363d611afc5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs that form a link farm, pointing to various domains, some of which are hosted on compromised CMS uploads. The primary purpose appears to be redirecting users through these links, potentially leading to phishing sites or malware downloads. No scripts were extracted, but the structure suggests a malicious intent to lure users to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9924

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 https://laborke.ru/uplcv?utm_term=autocad+drawing+to+pdf+online PDF link annotation
    • http://murasakijr.com/uploads/files/59697528829.pdfIn PDF document text
    • http://aiswaryamatrimonials.com/fck_uploads/file/zisalarizodobozudi.pdfIn PDF document text
    • https://itexpertdog.com/upload/files/61734196824.pdfIn PDF document text
    • http://konditsionery-reutov.ru/upload_picture/file/11318684623.pdfIn PDF document text
    • http://anhbanglaw.com/userfiles/file/40895889281.pdfIn PDF document text
    • http://lncxjzxxw.com/upload_fck/file/2021-5-23/20210523020547834075.pdfIn PDF document text
    • http://fontanarosaserigrafia.it/userfiles/file/43455661539.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608bccfae7b07---fuzigatanota.pdfIn PDF document text
    • https://aslimitada.com/userfiles/file/11992141467.pdfIn PDF document text
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2d5d9695f7---pusolatijixulupodizoxi.pdfIn PDF document text
    • http://alpanelektrik.com/depo/sayfaresim/file/vumetogexumavubezaniven.pdfIn PDF document text
    • http://delawaretravelmedicine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160844d5cd77a9---zutofitofegikunenan.pdfIn PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7fbb6607bc---xofamax.pdfIn PDF document text
    • http://dharmapremipariwar.org/userfiles/file/xekulupesezokup.pdfIn PDF document text
    • https://gearforfree.com/wp-content/plugins/super-forms/uploads/php/files/5gh369q5r1je3grcqu0uc4bd9j/17622298582.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4f5523487b---20173329629.pdfIn PDF document text
    • https://flvirginia.com/wp-content/plugins/super-forms/uploads/php/files/30f9b8af83a82c7e57899f724c61f132/turutinimejedeforirobobus.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/160aba56747e66---41511670742.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b5a482763f0---2332348744.pdfIn PDF document text
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afd7b664c65---marevebolekogov.pdfIn PDF document text
    • https://mobistore.co.nz/wp-content/plugins/super-forms/uploads/php/files/8397b6efc6141bde560f4c4685b47ee7/10041054776.pdfIn PDF document text
    • http://rydelko.pl/userfiles/file/31050360888.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ac2e277871b---dawanoka.pdfIn PDF document text
    • http://ptk-astana.kz/wp-content/plugins/super-forms/uploads/php/files/ec9209cc685c7f1afa897904b3657069/31268500174.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ddb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDB2 16496 bytes
SHA-256: 1306338ceba698edd1f1f7ce595a639315e4105a2a9157639b7b38023ae76aee
font_01_sfnt_off0000f4b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4B5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010ccc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CCC 10796 bytes
SHA-256: 519d50d10236ea776873c56a65d48ed765fbea9476e03ed5f4a35ffaba00649f
font_03_sfnt_off000125a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125A8 18420 bytes
SHA-256: ea45b1f12e1193dcd8d07795ec0b83ce7c2e691fa270fabe397cf3793028c2af