Malicious PDF — malware analysis report

Static analysis result for SHA-256 35219de0b190f52e…

MALICIOUS

PDF

86.1 KB Created: 2021-09-05 10:25:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 643d58d2a9d6df0924c51e3c0cda2611 SHA-1: 213faeda5703e03f688646dd5272624a2a490e83 SHA-256: 35219de0b190f52e8fd49362861b4e0a0b7ec36e5fc269c732ddc37dd822cdc9
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised websites or disposable domains, indicating a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly suggest this PDF is malicious, likely serving as a phishing lure or a distribution point for further malware. No scripts were extracted from this sample, but the extensive use of external links is the primary indicator of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://infrive.ru/uplcv?utm_term=modscan+64+manual PDF link annotation
    • https://beatmuellerfoto.ch/userfiles/files/sejuxadol.pdfIn PDF document text
    • https://elger.cz/fckphotos/file/80980953129.pdfIn PDF document text
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/f6fafeef7a949b82476cd7f3b7fbd2dc/46172680298.pdfIn PDF document text
    • http://go-trec.com/wp-content/plugins/super-forms/uploads/php/files/15jtroffseapnpnh01fcgbc13d/2055912395.pdfIn PDF document text
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/h7u5lqicf2mbatuunds06m1444/nefepugativanuxoviremu.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160850e1519b1b---wixug.pdfIn PDF document text
    • http://poltinik.ru/userfiles/file/minebarosevisutan.pdfIn PDF document text
    • http://www.prctech-th.com/ckfinder/userfiles/files/84115402870.pdfIn PDF document text
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c948221a4eb---60902884482.pdfIn PDF document text
    • http://group-anons.ru/userfiles/files/firezuzipubirikoxuje.pdfIn PDF document text
    • https://www.eoluk.com/wp-content/plugins/super-forms/uploads/php/files/k45kaptbppp97v8nb5657b6tiv/kotos.pdfIn PDF document text
    • http://lycee-elm.org/userfiles/file/15571811444.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609859324e67e---34953399125.pdfIn PDF document text
    • http://zae.me/datafiles/file/gokob.pdfIn PDF document text
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a159cf37895---32944282493.pdfIn PDF document text
    • https://sakesushimn.com/userfiles/files/sirajiluzasimubidajozezim.pdfIn PDF document text
    • https://www.skyline-recruiting.com/wp-content/plugins/super-forms/uploads/php/files/98c584a83f307c4cbefbc95bce0bcd1b/79682639282.pdfIn PDF document text
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/pj4gnki1av0pphbfp6jcuja0t1/guduzobowexe.pdfIn PDF document text
    • http://mlight.cz/archiv/file/jarikuxitogejazeletofe.pdfIn PDF document text
    • http://formel1vermietung.de/userfiles/file/55453277544.pdfIn PDF document text
    • https://www.sixteengrams.com/wp-content/plugins/super-forms/uploads/php/files/usboqimcn9q10kqusfsabvnhuc/51541380784.pdfIn PDF document text
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1608291414078d---79598737498.pdfIn PDF document text
    • http://slp61.com/clients/e/e2/e296dcecfd7d10ffef0cc83fef253c72/File/kexijebuw.pdfIn PDF document text
    • http://kraemer-duennebacke.de/files/file/52586728793.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_off0000eacf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEACF 18608 bytes
SHA-256: 22e45173ea78a793674d4c79bdf9e7943c189655d8ea702e4f46864f6179e6c4
font_01_sfnt_off00011b56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B56 10448 bytes
SHA-256: 583c4af98fb4a71487e038a0228c6813b76627eb41406ca43ee427f7948f9205
font_02_sfnt_off00013312.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13312 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1