Malicious PDF — malware analysis report

Static analysis result for SHA-256 3100895babc7c577…

MALICIOUS

PDF

71.7 KB Created: 2021-09-27 22:55:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 2aa2b1c4bc4e34db2362fa7e80cf1682 SHA-1: 38536dbe8ee74d9167cbee46b9b93887f475e715 SHA-256: 3100895babc7c5775793d4115e331d48c59a4f0982a47883edbbdb5fbaf5e429
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://bumsnab.ru/uploads/files/ginonom.pdf In PDF document text
    • http://fuguchair.com/upfolder/e/files/20210908053433.pdfIn PDF document text
    • http://elmbbq.com/uploads/files/sexaz.pdfIn PDF document text
    • http://chuaphucluong.com/uploads/image/files/jerunedimafutaduzuweri.pdfIn PDF document text
    • http://fotografoenricogiampieri.it/userfiles/files/93418390371.pdfIn PDF document text
    • https://mebelihome.ru/upload_picture/zidup.pdfIn PDF document text
    • http://cecev.com/stockages/files/ronar.pdfIn PDF document text
    • http://austral-immo.com/userfiles/files/gunipasosiref.pdfIn PDF document text
    • http://rosg.net/sa_upload/userfiles/file/20210916103653.pdfIn PDF document text
    • http://leinerpakgelatine.com/survey/userfiles/files/xamitemapusuzogiweputowu.pdfIn PDF document text
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/fe1ead92df9eb24eafb290f3350eac36/virepij.pdfIn PDF document text
    • http://sntaviator.ru/ckfinder/userfiles/files/fidusafagobanotufatur.pdfIn PDF document text
    • https://loonbedrijfschimmel.nl/userfiles/files/boxukisuzekoxigenalovibe.pdfIn PDF document text
    • http://bon-mar.com/fck_user_files/file/nibusi.pdfIn PDF document text
    • https://lawyerupsmart.com/tempimg/file/74029483569.pdfIn PDF document text
    • http://brandnewgoods.net/userfiles/file/ditigav.pdfIn PDF document text
    • http://hissekurban.com/resimler/files/wupatamesexejekemut.pdfIn PDF document text
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/1614b77c200ed7---vozawurobun.pdfIn PDF document text
    • http://kantipursecurity.com/userfiles/file/91789953173.pdfIn PDF document text
    • http://designklasse.de/ckfinder/userfiles/files/gujobasurup.pdfIn PDF document text
    • https://cometgroupinternational.com/ckeditor/ckfinder/userfiles/files/57203541267.pdfIn PDF document text
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/161393e9622352---86497237313.pdfIn PDF document text
    • https://xn--nmqu14inmf.com/upload/files/99729217679.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=codes+for+anime+dimensionsPDF 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_off0000b26c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB26C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ca7e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA7E 18348 bytes
SHA-256: 3e3b018dab07e2a47a8328a747789266716f5f8e236ae08458c602847fc194de
font_02_sfnt_off0000f9ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9FF 10400 bytes
SHA-256: b7a11680f00bdc6b4b05e77242b17a1541e0eb8e7527a87a047d4161bbaef822