Malicious PDF — malware analysis report

Static analysis result for SHA-256 82bd4cf937fa4bc7…

MALICIOUS

PDF

74.1 KB Created: 2021-09-20 01:05:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 871023c5b8b0ed674634b0a3de04e137 SHA-1: bc79b0a9bb3c85f44b2ea18d914c7e4ed69742dd SHA-256: 82bd4cf937fa4bc76a6686f76ea7033042f45d10f38eaf147d33db39558273ff
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs that point to various domains, many of which appear to be part of a link farm designed to obscure the ultimate destination. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for these links, suggesting an attempt to evade detection and distribute malicious content. While no scripts were explicitly extracted, the nature of the embedded URLs and the overall detection suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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=android+tv+app+for+live+tv PDF link annotation
    • https://aldurra.ly/images-editeur/img/file/72167288366.pdfIn PDF document text
    • https://0800-707-808.com/upload/ckfinder_temp/files/20210919191821.pdfIn PDF document text
    • http://chizclean.ru/files/fck/file/nodajikivonutanawulogad.pdfIn PDF document text
    • https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/623ipb0rajtnj60ntp4msnmtru/kubigoluxed.pdfIn PDF document text
    • http://ranchobg.com/img/file/gaxatiwenejon.pdfIn PDF document text
    • http://flooroverstock.com/admin/userfiles/file/dijali.pdfIn PDF document text
    • http://esejsc.com/upload/files/busolerumovusufirom.pdfIn PDF document text
    • http://myucpb.com/userfiles/file/nilezedemefevutol.pdfIn PDF document text
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/3qg4466rrghhh3u3nfamihupjr/tufop.pdfIn PDF document text
    • https://vsetinrally.cz/userfiles/file/3512033836.pdfIn PDF document text
    • http://runbo.net/upfiles/files/16314102801836.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139b5e8d9173---sutinunegesegixojoxove.pdfIn PDF document text
    • http://tznjl.com/userfiles/files/68177570409.pdfIn PDF document text
    • http://oecschool.com/userfiles/file/muzaralorepibeganul.pdfIn PDF document text
    • http://orem.mn/uploads/files/32737892027.pdfIn PDF document text
    • http://a-xian-coat.com/uploads/files/202109170528372492.pdfIn PDF document text
    • http://tiquital.com/documentos/file/xovowijaf.pdfIn PDF document text
    • http://beverly.kopanramen.com/uploads/files/kuxesimum.pdfIn PDF document text
    • http://xn--b1agjlwjc3g.xn--p1ai/ckfinder/userfiles/files/71979876871.pdfIn PDF document text
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/609edb0a2a2acd2f116f3d588f7de6c1/botajuwijamini.pdfIn PDF document text
    • http://on-video.com/movies/movie_data/file/87676196969.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_off0000c14b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC14B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d95d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD95D 16364 bytes
SHA-256: ef664cd6983a3d5208527b1d9ed2c06b7996b742f378ba887ad78f532010fdc7
font_02_sfnt_off0001036c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1036C 10368 bytes
SHA-256: 84e1c792ef6b62c1646cf6d9c6a81a0ab9f6ca9e62ef91403d4301ed14eca500