Malicious PDF — malware analysis report

Static analysis result for SHA-256 d846cff257a0ac4c…

MALICIOUS

PDF

94.4 KB Created: 2021-06-28 02:44:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: c9bc464d3b3a204c523be349dfeef985 SHA-1: 46fc9d163017eb7dec569aad2ec8d28b38301ed1 SHA-256: d846cff257a0ac4c4383067500c4e4f33f9ab003aa91f9204a954def0ca2f6bb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File

The PDF file contains numerous embedded URLs that point to compromised WordPress sites, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of multiple distinct hosts and the use of 'utm_term' parameters in some URLs suggest an effort to obscure the ultimate destination and potentially track campaign effectiveness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9806

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://inwebjor.ru/uplcv?utm_term=free+printable+family+feud+questions+and+answers PDF link annotation
    • https://eyestech.in/wp-content/plugins/super-forms/uploads/php/files/47vc62i6vh4sqqbshqf6p8s9th/busituniz.pdfIn PDF document text
    • https://www.perfumista.co.uk/wp-content/plugins/super-forms/uploads/php/files/325515d60d9280cdcadef3552d529358/zunipixepoluw.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/16091b9743c4fa---gatozewu.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160936cf663f77---39366066437.pdfIn PDF document text
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/160780f25bf17a---76360839408.pdfIn PDF document text
    • http://payassistinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094abdc265c4---kumigilabe.pdfIn PDF document text
    • https://forumhotel.by/wp-content/plugins/super-forms/uploads/php/files/4td9cdtsigc517q7784d17bt17/32188455406.pdfIn PDF document text
    • https://melz-feu.ru/upload/93938194959.pdfIn PDF document text
    • https://hitpoint.tw/userfiles/file/90674086668.pdfIn PDF document text
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fa2d2382ae---vemekoxor.pdfIn PDF document text
    • http://www.veronicaneal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/1607c2ec2d9253---21497535477.pdfIn PDF document text
    • https://earplighting.com/wp-content/plugins/super-forms/uploads/php/files/5c50b0a5373f69a0fc805cd04a48e87f/riduxipafer.pdfIn PDF document text
    • https://www.actionconstructionjax.com/wp-content/plugins/super-forms/uploads/php/files/ec12e8a8b5547646a92116b82205ce18/wigexuredofojawat.pdfIn PDF document text
    • http://decaiyun.com/upload/file/210611151452217345jt80b3g79vgf.pdfIn PDF document text
    • https://al-farh-iq.com/upload/userfiles/file/duvetavemapoka.pdfIn PDF document text
    • http://dermalab.pl/userfiles/file/lizejasisawifimopekajape.pdfIn PDF document text
    • http://www.pilonidalsinus.gen.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160774329e91e5---77542278098.pdfIn PDF document text
    • https://shop-ecobati.com/medias/upload/files/rorabufupodide.pdfIn PDF document text
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c49c1271743---71234248499.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b95c859fb8a---vipik.pdfIn PDF document text
    • http://c2r-auto.com/uploadfiles/file/2021060118123373499.pdfIn PDF document text
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/ccc1fadde95f28ebd356a677e66d6ed9/bawobe.pdfIn PDF document text
    • https://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/9dac15f942f0abab1f1cb78a876ea337/79981944688.pdfIn PDF document text
    • http://odmooregolf.com/clients/e/e7/e7046aca88cfcc92de0be8f3f6b3de3d/File/35413994925.pdfIn PDF document text
    • https://agentcctv.com/userfiles/file/palijezuzunikegawakutamu.pdfIn PDF document text
    • http://wisdomtours.net/upload/file/5221875985.pdfIn PDF document text
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16098302551bcc---34156947354.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_off00010be4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BE4 11220 bytes
SHA-256: 75517033473468319613bd49d5f3ed9199d96c3f476b32a6be195adc18de3446
font_01_sfnt_off000125c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125C2 17516 bytes
SHA-256: c896e213481d984c250f156b3e2f318729a38803bd812ff13526895a9902aacf
font_02_sfnt_off00015388.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15388 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1