Malicious PDF — malware analysis report

Static analysis result for SHA-256 77f53b78674612ef…

MALICIOUS

PDF

90.4 KB Created: 2021-09-16 03:29:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8d325cf9d52c27436d9ac91fdbabdc65 SHA-1: 5ece193acd261bdd16c4f93e55ae9e06da50dbf9 SHA-256: 77f53b78674612ef62906369e3038a9ab5e96a494c866771960e5c6b07443bd3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the document's purpose is to host a large number of links. No scripts were extracted from this sample, but the overall structure and URL distribution point towards a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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=how+to+open+ports+on+android+tethering
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613991e233531---gadudapafiz.pdf
    • https://jsptti.com/ckeditor/ckfinder/userfiles/files/xipuvozezopuzavavafetuwel.pdf
    • http://childconnect.com/swi/fckfiles/file/23670093934.pdf
    • http://hotstamping.pl/files/file/vilitagi.pdf
    • http://winfielddeli.com/ckfinder/userfiles/files/goxaduloxilunobu.pdf
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/161354cacbcb78---78670839286.pdf
    • https://uleiuri.ro/userfiles/file/45214751644.pdf
    • http://cmtoolsrental.com/user_img/files/29355125773.pdf
    • http://saopauloairporttransfers.com/ckfinder/userfiles/files/vumeloxutojoti.pdf
    • http://nsfeed.com/_UploadFile/Images/file/juraxadarazowiliwi.pdf
    • http://thueotodn.com/uploads/image/files/sibekesor.pdf
    • https://cosmopolitanhotel.eu/uploads/wysiwyg/files/jibanakesu.pdf
    • http://ettermanenterprises.com/ckfinder/userfiles/files/41554500710.pdf
    • https://amursvoidom.ru/media/files/fesovakuzaziwu.pdf
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/161380a5ea4dde---8006236762.pdf
    • https://syteq-pro.com/userfiles/file/51998631972.pdf
    • https://dellrein.ru/content/file/67114555645.pdf
    • http://355353.ru/userfiles/file/xijejikoxukufinadis.pdf
    • http://donghozibistore.com/luutru/files/38631531038.pdf
    • https://wcfkenzi.com/ckfinder/userfiles/files/72668591280.pdf
    • http://swaminarayangm.org/userfiles/file/27632551205.pdf
    • https://dubaimotorcycletours.com/uploaded_images/files/wijil.pdf
    • https://stehovani-ostrava.cz/static_pages_files/file/dipuja.pdf
    • https://officialbacknumber.org/editor_up/girazadefir.pdf
    • 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_off0000fa32.bin
216243eba02bfd668c2601856a645831420fccbe18327a386bcf925898309bf6
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA32 18900 bytes
font_01_sfnt_off00012ae1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12AE1 16792 bytes
font_02_sfnt_off000142f8.bin
72ee4c7db674184eb208d159788f9043598a24f788902f7f7c0352beb8452ac9
pdf-font-stream PDF embedded font (sfnt) at offset 0x142F8 10704 bytes