Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4138abb1e09b3c4…

MALICIOUS

PDF

88.3 KB Created: 2021-07-16 18:02:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: c79778f149dae502be87786404f24389 SHA-1: c5be0325e381876a458bcaeac599fb54d835b6ba SHA-256: a4138abb1e09b3c4d562e2cf3a32579a9f05eb9f4229730bbe3ae57753788e0d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious. It contains numerous links pointing to external websites, many of which are hosted on compromised CMS platforms or disposable domains, suggesting a link farm or phishing lure. The presence of embedded URLs and the overall structure indicate an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://wamer.org/userfiles/file/11846698790.pdf In PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/o7cbi1977oqbc9p5lgo3lon1s7/90824964064.pdfIn PDF document text
    • http://videoacceso.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfae970c251---57816430798.pdfIn PDF document text
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/69aff4e7fa241ce299f36b9346f3957a/tufesidetet.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/1606f73df4c82c---38414278093.pdfIn PDF document text
    • https://rfcorporation.net/wp-content/plugins/super-forms/uploads/php/files/7035a5e30be1770161ce41399872d20e/fobeguzexagalogiwev.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e9a578b97f---77798863461.pdfIn PDF document text
    • http://medicamarsala.it/userfiles/files/23004293886.pdfIn PDF document text
    • http://jedwines.com/cmsCart//upload/file/68330495931.pdfIn PDF document text
    • https://cplastik.cz/data/cms/file/37157890011.pdfIn PDF document text
    • http://artpolinakuzina.ru/pict/file/zuwefep.pdfIn PDF document text
    • http://xn--e1aaafipco3bk8gra3b.xn--p1ai/upload_picture/file/jugupekurowuxotulilivikid.pdfIn PDF document text
    • https://atlanthealth.com/wp-content/plugins/super-forms/uploads/php/files/5556f388840d874c4f7ab5aaaab3ed65/pojosurobekuseraduvodijaf.pdfIn PDF document text
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c536e7f006---59626414142.pdfIn PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c8518f53263---61752638696.pdfIn PDF document text
    • http://baobianhkhang.com/upload/files/supilemopij.pdfIn PDF document text
    • https://www.albispanaderia.com/wp-content/plugins/super-forms/uploads/php/files/27ee5ae58480cc50093269c66a1860a6/41184179530.pdfIn PDF document text
    • http://nacyc.jp/Upload/file/bubogigozanifisafenopi.pdfIn PDF document text
    • https://best-label.com/upload/files/60061308196.pdfIn PDF document text
    • https://www.electriclighting.com/wp-content/plugins/super-forms/uploads/php/files/5f1ef71f54d130252b5944387ce68fcd/jinekijoxuputube.pdfIn PDF document text
    • https://directorvincentchow.com/fck_filemanager_upload/file/80180784614.pdfIn PDF document text
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1606c97abc43c6---narezemuwuponitawoxemuno.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=fabby+photo+editor+app+downloadPDF 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_off0000f85d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF85D 10636 bytes
SHA-256: 8f96c73dbdc5825ce425af5bc0b0574bf84216cbae3abbe5fdb0baba0b939fd5
font_01_sfnt_off0001106f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1106F 16796 bytes
SHA-256: 453e9b073af6d855334bec280f8731f712da84a7a9d3a47fd2766460839ca9ac
font_02_sfnt_off00013c3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C3C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1