Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c51c91a0182466b…

MALICIOUS

PDF

70.0 KB Created: 2021-10-02 10:45:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 32911027f13d5956924546bee98b6bce SHA-1: 308945f33773ca777ebbc6905a9b6a5d4794ac67 SHA-256: 3c51c91a0182466b6220c22395acad2b56c8731d7900d32b93f82d1d6c42c59c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics as malicious, including a high ML score and ClamAV detection. It functions as a link farm, directing users to numerous external URLs, many of which are hosted on compromised CMS upload directories or disposable hosting. These links likely lead to phishing pages or further malware downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://wastran.ru/uplcv?utm_term=beef+and+ox+tripe+in+chili+sauce PDF link annotation
    • https://by-express.com/upfiles/editor/files/78971887732.pdfIn PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16142077e330a7---31595210291.pdfIn PDF document text
    • http://kondicionery-bronnitsy.ru/upload_picture/file/49640293501.pdfIn PDF document text
    • http://milwaukee.center/userfiles/file/lepabuvufewi.pdfIn PDF document text
    • https://zemtechnika.lt/public/site/0files/gifinuravob.pdfIn PDF document text
    • https://felicitareonline.ro/ckfinder/userfiles/files/4095338458.pdfIn PDF document text
    • http://minuspk.ru/minuspk.ru/userfiles/file/zanovumojumitavagukovuke.pdfIn PDF document text
    • https://deniz-sogutma.org/img/userfiles/file/63730634831.pdfIn PDF document text
    • http://eternoohydro.com/d/files/49957893485.pdfIn PDF document text
    • http://chinajnbt.com/images/upload/File/56352355453.pdfIn PDF document text
    • http://bassonconsulting.mc/userfiles/file/93202028103.pdfIn PDF document text
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/afd9d378ed7e07e15975b85433bb47fb/40998709264.pdfIn PDF document text
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/16152cae1f3dfa---11134625361.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140f2e087bab---40691043727.pdfIn PDF document text
    • https://masihpt1.com/contents/files/14867033056.pdfIn PDF document text
    • http://7serve.org/userfiles/file/20211002155104.pdfIn PDF document text
    • https://www.thecandystoresudbury.com/wp-content/plugins/super-forms/uploads/php/files/q5g2d86cv1d1lpldg7kfescfqh/lebosexixujezab.pdfIn PDF document text
    • http://ototavandosemesi.com/resimler/file/zevivijaxijezagefuguzilip.pdfIn PDF document text
    • http://jimsclub.net/new/board/img_tinfo/file/20210901104514.pdfIn PDF document text
    • https://buzascsaba.hu/userFiles/file/vukefetovup.pdfIn PDF document text
    • http://architectureanddesign.it/userfiles/files/bodatugiwatalirorekag.pdfIn PDF document text
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/1614340b262567---70024927217.pdfIn PDF document text
    • https://sklep-pinokio.pl/web/uploads/files/dogazalezesifo.pdfIn PDF document text
    • http://dossalas.com/wp-content/plugins/super-forms/uploads/php/files/8913235778cc9a4ee9acb2409e95af9f/vaduguziwiva.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_off0000b34f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB34F 14948 bytes
SHA-256: cb964c94e73850c635eb30c2501bb14f8515d163cb1d65fb00a366a2cf19569e
font_01_sfnt_off0000d8d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8D7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f0ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0EE 10972 bytes
SHA-256: 7a54830fbfd3213951b9ea904953bd9369a2781398bbb485d76a412d69b007dc