Malicious PDF — malware analysis report

Static analysis result for SHA-256 0c0c4e51766ce455…

MALICIOUS

PDF

88.8 KB Created: 2021-08-13 12:59:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: d0697d7d565f937c366dbc12ac266311 SHA-1: 94bb350647a9a2bb6769792db8d37a0c7c1add2a SHA-256: 0c0c4e51766ce455774799a0d02a91d249901bc7f86ffc7c5466133c97c60769
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous URLs pointing to compromised WordPress uploads and disposable hosting, forming a link farm. While no scripts were explicitly extracted, the nature of the link farm suggests an intent to redirect users to phishing sites or download further malicious content, aligning with spearphishing attachment tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://istanbulbalbir.com/upload/ckfinder/files/27545921548.pdf In PDF document text
    • https://www.synergyheart2heart.team/wp-content/plugins/super-forms/uploads/php/files/9jank0u7flgn0grtfh3q16496k/timatawopife.pdfIn PDF document text
    • https://farmstead.tw/farmstead/upload/files/45240377164.pdfIn PDF document text
    • https://bititechnika.com/uploads/file/luzefoti.pdfIn PDF document text
    • http://technoculture.cz/admin/upload/file/42217635205.pdfIn PDF document text
    • http://provia-events.de/pics/fotos/1/file/bikojis.pdfIn PDF document text
    • http://speckrepeg.by/UserFiles/files/dodilopasavumeke.pdfIn PDF document text
    • http://www.fullertherapy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f45e70e560---23452914008.pdfIn PDF document text
    • http://mousike.it/img_ins/files/xifinalebaz.pdfIn PDF document text
    • https://publicbridge.pl/userfiles/file/88202647824.pdfIn PDF document text
    • http://schouteninterieurwerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160828b4e3fc15---73772259339.pdfIn PDF document text
    • https://polskieplytki.com/wp-content/plugins/super-forms/uploads/php/files/4c3ffdd4b7cc78d2fcdf106325c27785/62036530548.pdfIn PDF document text
    • http://porpora.biz/imagenes/imagenes_contenidos///64096103425.pdfIn PDF document text
    • https://spcinternational.in/ckfinder/userfiles/files/74644068325.pdfIn PDF document text
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085bc2930009---45077969335.pdfIn PDF document text
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f2c6e465e0---zumepivosefinewi.pdfIn PDF document text
    • http://foire-fromages-et-vins.com/wp-content/plugins/formcraft/file-upload/server/content/files/160810a04ca97a---minamejelejexuwifobidex.pdfIn PDF document text
    • https://www.djluk.co.uk/wp-content/plugins/super-forms/uploads/php/files/iddb84to9mcd19emgkvl7vqq3p/74928494033.pdfIn PDF document text
    • http://www.feniuniversity.edu.bd/app/webroot/ckfinder/userfiles/files/97524415256.pdfIn PDF document text
    • http://prospekt-rostov.ru/ckfinder/userfiles/files/708135551.pdfIn PDF document text
    • https://www.brightfieldbusinesshub.co.uk/wp-content/plugins/super-forms/uploads/php/files/3dsolm4i0hvinc8mbnfcmcn0gs/93070249498.pdfIn PDF document text
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/f5b94694b5cb3cbce6a1f28702d7e746/zamoviw.pdfIn PDF document text
    • https://thedestinbeachhouses.com/wp-content/plugins/super-forms/uploads/php/files/0d6709d03f3894a024983e77dee34c93/lobegavum.pdfIn PDF document text
    • http://aps-mes.com/files/file/galifexupopi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=reading+comprehension+exercises+b1PDF 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_off0000f3f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3F8 18380 bytes
SHA-256: 7f2939818a60cf8cff270d472f5a343212e9c19952b4ea46f7006b83ba929155
font_01_sfnt_off000121f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121F6 11156 bytes
SHA-256: 203be898d382c401b9d20d9938ab864c2938cfb99e7239a6c04b0d63e34b0863
font_02_sfnt_off00013b64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B64 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1