Malicious PDF — malware analysis report

Static analysis result for SHA-256 20c808d5b3f0502f…

MALICIOUS

PDF

77.5 KB Created: 2021-09-05 00:21:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 12f6a67a2194d1ecf85e6c7d5c8625f6 SHA-1: 0b546e70a91487222402f50f5046453de8ae6426 SHA-256: 20c808d5b3f0502f0c3c430b0c723199d68ca0827810431ef92cfaa8207e20b8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links to external PDFs hosted on compromised WordPress sites and disposable domains, indicating a link farm designed to redirect users to malicious content. While no scripts were explicitly extracted, the PDF structure and heuristic firings suggest it's designed to exploit vulnerabilities or lead users to phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

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 http://www.ellisrasbetonwerke.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a72c14607a1---bodojomakop.pdf In PDF document text
    • http://geometrabottero.it/userfiles/files/zetalevovisax.pdfIn PDF document text
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/dvgv4946dut2m073bs3ibof4uc/58869752754.pdfIn PDF document text
    • http://www.orarestauratorisaf.it/wp-content/plugins/formcraft/file-upload/server/content/files/160ec4b044cd61---nezinuzopi.pdfIn PDF document text
    • http://word.mn/uploads/assets/tuzuzobigaziletavisunekeg.pdfIn PDF document text
    • http://www.asslar.de/downloads/jasiluluvow.pdfIn PDF document text
    • http://gerocuki.hu/user/file/tuxixajiwimexibe.pdfIn PDF document text
    • https://www.skyline-recruiting.com/wp-content/plugins/super-forms/uploads/php/files/70a226e4b37a3bef9f7582edc6996d03/51119753350.pdfIn PDF document text
    • http://strap.sk/uploads/files/52572133873.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610070905b3c0---wuzusilakiwegolunup.pdfIn PDF document text
    • https://stcc-sa.com/motakamel/Ups/files/41221135791.pdfIn PDF document text
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/79c856a730291d7eb670af3a0e6dd5cc/timusanaxo.pdfIn PDF document text
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160b5b5d5892b0---97586041289.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/160bbb9e694e8a---wukaka.pdfIn PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613292e09e1af---9549491607.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1d8b85eab9---55430211401.pdfIn PDF document text
    • http://gesundezellen.de/neu/userfiles/file/nifujavejasuju.pdfIn PDF document text
    • http://coffee33.ru/archive/file/59105167536.pdfIn PDF document text
    • http://tinhdaurosa.com/Images_upload/files/fikigorit.pdfIn PDF document text
    • https://celebicatering.com/upload/ckfinder/files/kuleruzekal.pdfIn PDF document text
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/6596d4171132e3633a0562201b0f39c6/53225970952.pdfIn PDF document text
    • https://mehreganimaging.ir/images/upload/files/37298974769.pdfIn PDF document text
    • http://thanhnhomdinhhinh.net/uploads/files/tuvosoravob.pdfIn PDF document text
    • https://frontiersneurophotonics.org/wp-content/plugins/formcraft/file-upload/server/content/files/1/160ba185b0f281---sazivine.pdfIn PDF document text
    • https://beautyyaurient.com/editor_upload/file/texuwiputadetakizaf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=catholic+hymn+book+2017+pdfPDF link annotation
    • 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_off0000c97e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC97E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e190.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE190 17260 bytes
SHA-256: 7cdd2e00c9052ac61e209ba56a076cacfea89ceb2bb06feeaae191200764ed4f
font_02_sfnt_off00010e87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E87 11208 bytes
SHA-256: 3cf6ed761eb1e266e607606f8bcf1264a1727101846cbe0c7c6ae76a0fdd37c3