Malicious PDF — malware analysis report

Static analysis result for SHA-256 9fdf6f00cb843646…

MALICIOUS

PDF

73.2 KB Created: 2021-09-07 06:53:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 87e208764a598521d873a153b1374fe3 SHA-1: 7a66216ceb79613b17b2405b5358cc477998f8f5 SHA-256: 9fdf6f00cb843646a302fc674b1ee691852b9a9f843accea670e3639672bb6cf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to numerous compromised WordPress sites and disposable hosting, suggesting an attempt to distribute phishing content or malware. The embedded URLs, such as https://nomylo.ru/uplcv?utm_term=how+to+manually+update+android+on+asus+tablet, are likely used to redirect users to malicious destinations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9885

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://nomylo.ru/uplcv?utm_term=how+to+manually+update+android+on+asus+tablet PDF link annotation
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/aeb697d763f23c11ec8f2c08d325fd6e/90663548427.pdfIn PDF document text
    • http://uitetenindex.nl/images/uploads/27012267135.pdfIn PDF document text
    • http://skrabl.pl/www/rpbd/fck/file/7660404013.pdfIn PDF document text
    • https://tapuionoticias.com/ckfinder/files/nomusimutulaka.pdfIn PDF document text
    • https://limsurempat.com/contents//files/vuvetazegopazul.pdfIn PDF document text
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7054545914---subewemedadijofirorol.pdfIn PDF document text
    • http://istrouma1971.com/clients/9/9b/9b88b062b8d6af44b28e209fcb06d7d5/File/77924605324.pdfIn PDF document text
    • https://kalyna.ua/sites/default/files/userfiles/file/fenabeteki.pdfIn PDF document text
    • http://first-group.kr/ckupload/files/dajapivalogepuma.pdfIn PDF document text
    • http://atsrealtyvietnam.com/upload/files/gapefejuw.pdfIn PDF document text
    • http://vksraja.in/fckeditor/upload/file/41342387160.pdfIn PDF document text
    • https://swift-tw.com/lcc/upload/files/mozevexorobatoz.pdfIn PDF document text
    • http://edilgroupdigiovanni.it/userfiles/files/21146176511.pdfIn PDF document text
    • https://justbuymeds.net/userfiles/file/54695390884.pdfIn PDF document text
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a6f91fb82d1---1024372638.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160e0e614a976f---54936691380.pdfIn PDF document text
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608539f1f1a88---4275471262.pdfIn PDF document text
    • http://techbico.vn/uploads/image/files/nuriwefobetedederirepidom.pdfIn PDF document text
    • http://fw-simple.com/uploads/files/10248624905.pdfIn PDF document text
    • http://palenice.net/obrazky_clanky/file/ginidabowegefutinonegamu.pdfIn PDF document text
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611fcd97890b5---119944998.pdfIn PDF document text
    • http://szao-spb.ru/images/news/file/12650570998.pdfIn PDF document text
    • https://vannordenvastgoed.nl/userfiles/file/dexidosexuvuwopipituzene.pdfIn PDF document text
    • http://gusanhightec.com/userData/board/file/fikevufuzesidigili.pdfIn PDF document text
    • https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161357ce9cf6fd---48770440287.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c69a4f476fd.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607abec2beeaf---riwawujotizukota.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_off0000bd06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD06 15832 bytes
SHA-256: 32cb812d15431525adf616f8a985a6848c41066a1392bacb20ca96ddb070f925
font_01_sfnt_off0000e5b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5B0 10984 bytes
SHA-256: 20bb058b677d3e178764cee614ee88801323ab15f08c1b0112ee57069770e448
font_02_sfnt_off0000fefd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEFD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1