Malicious PDF — malware analysis report

Static analysis result for SHA-256 70c877f1dc54dfa3…

MALICIOUS

PDF

71.6 KB Created: 2021-09-04 12:23:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 86a989798a00a57c779f175f2eb1487a SHA-1: 72362492370a91cf5717f16a3250c1e1a6117846 SHA-256: 70c877f1dc54dfa39c3a50e379bd034b5aa9283f958b0222825167c523cb4150
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs, many pointing to compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM suggests a tactic to obscure the true destination by using many distinct, low-reputation hosts.

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://mt-creativestudio.com/ckfinder/userfiles/files/28103273971.pdf In PDF document text
    • http://ahkkpcm.org/userfiles/45403538195.pdfIn PDF document text
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607e2cc197425---60121465956.pdfIn PDF document text
    • http://cartopack.be/Images/file/58470469054.pdfIn PDF document text
    • https://www.beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/eaf4f979eeb258f0ebf364ff412990cd/muwemutokuxuj.pdfIn PDF document text
    • https://truckforceone.eu/upload/editor/file/pulurafawexa.pdfIn PDF document text
    • http://castrolmintabolt.hu/images/upload/file/temevarasiw.pdfIn PDF document text
    • https://postelezmasivu-ostrava.cz/ckfinder/userfiles/files/pokamikonigananodo.pdfIn PDF document text
    • http://mediacast.vn/ckeditor/upload/files/winikutodizusa.pdfIn PDF document text
    • http://bocghebinhduong.com/media/ftp/file/78615786668.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f397aef86e---rizatekokabus.pdfIn PDF document text
    • http://martonaroniskola.net/userfiles/file/30292293685.pdfIn PDF document text
    • http://suseefinance.com/userfiles/file/36921343146.pdfIn PDF document text
    • http://acpiindia.com/userfiles/file/28712610620.pdfIn PDF document text
    • https://renesens21.com/ressources/upload/files/datifirowajad.pdfIn PDF document text
    • http://iccjsc.com/images/uploads/files/fetesixovofej.pdfIn PDF document text
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/5e0d0bf6c65edd664ebb93e3364b4c73/fuvogonunasevunigu.pdfIn PDF document text
    • http://polyacer-ecp.com/userfiles/files/20210903_164522.pdfIn PDF document text
    • https://bahia-group.com/ckfinder/userfiles/files/59560957043.pdfIn PDF document text
    • http://iwish-cosmetics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e5a2bf413f---5345360341.pdfIn PDF document text
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16074d95bc78c8---52033971337.pdfIn PDF document text
    • http://xpeedon.net/userfiles/file/20210801054210.pdfIn PDF document text
    • http://dmhu.eu/uploads/uplib/file/xudaniri.pdfIn PDF document text
    • http://maxtarget.by/ckfinder/userfiles/files/nirukefager.pdfIn PDF document text
    • http://detikakdeti.ru/img/file/21639941054.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=free+download+pdf+reader+for+laptopPDF 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_off0000b776.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB776 16320 bytes
SHA-256: 5a9fdf846ffeec3f5dad0643343382b5d31865c9d04a66795e9492681c89eb16
font_01_sfnt_off0000e16f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE16F 10296 bytes
SHA-256: 3034de0ca3063292c38cef3930f6eb60466b1b2d5f5ae7b8c27240f2499bde4b
font_02_sfnt_off0000f8c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8C5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1