Malicious PDF — malware analysis report

Static analysis result for SHA-256 85b5198806b8df31…

MALICIOUS

PDF

93.1 KB Created: 2021-08-05 18:07:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: f17a7ea1a47c3e6ccc489d39b6af11ca SHA-1: 0c366d7ec23d1c8922ee69792d7227c2c988a52a SHA-256: 85b5198806b8df317723ddb80170c9902df2915103286c5e002daa552d42a9c3
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 compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL heuristics and the presence of a link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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 https://recapress.com/ckfinder/userfiles/files/45898950088.pdf In PDF document text
    • http://alrabbanoilandgas.com/file/files/80579779751.pdfIn PDF document text
    • https://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/julntnc9rp5q7423kiorjmg505/93176585210.pdfIn PDF document text
    • http://jarosi.hu/files/file/razasogamopufedowe.pdfIn PDF document text
    • https://emotionalgift.com/ckfinder/userfiles/files/benufoputatulij.pdfIn PDF document text
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/0f5dd7c63e323c752e01af97038bdee3/23005336111.pdfIn PDF document text
    • https://hotellemaritime.com/hotel/upload/files/xarivilozafoxu.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097b02e366ce---jiferewejidasiwaloti.pdfIn PDF document text
    • http://seigyobannkaigaikikaku.com/ckfinder/userfiles/files/nuvubabisiz.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608a113780b88---budivukemibusuzar.pdfIn PDF document text
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16096538cc8515---49319055748.pdfIn PDF document text
    • https://www.eziblank.com/wp-content/plugins/super-forms/uploads/php/files/gad4bvodeogo878n2a0pm64c15/lizilasixevupuwilafewil.pdfIn PDF document text
    • http://parzenica-bialka.pl/userfiles/files/jaferexarajinafomijufe.pdfIn PDF document text
    • https://appvid.eus/userfiles/files/bexuzebibitamurobodoriwon.pdfIn PDF document text
    • http://melly-incendie.fr/img_db/62955866135.pdfIn PDF document text
    • https://www.waterlooarmsnewforest.co.uk/wp-content/plugins/super-forms/uploads/php/files/2d49c5c10edc7e150727d993b28e45e4/42712682212.pdfIn PDF document text
    • http://www.petersmetalstitching.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160868bf565353---muxubosepusup.pdfIn PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/6l1gbuskrl7fvjc0r344db901o/gadiw.pdfIn PDF document text
    • http://asea-admin.com/_userfiles/file/20210515211925.pdfIn PDF document text
    • http://msci.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/1608d2e628702a---1000245599.pdfIn PDF document text
    • https://anfauglir.com/images/file/30677255884.pdfIn PDF document text
    • https://chetanaus.org/bheru/uploadfiles/file/31941393422.pdfIn PDF document text
    • http://studiotravenzolo.it/userfiles/files/86923243415.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=how+to+open+locked+bosch+washing+machine+doorPDF link annotation
    • http://e1pl2.nazwa.pl/busy/fotki/file/rupago.pdfIn PDF document text
    • 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_off00010686.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10686 17408 bytes
SHA-256: a72e27ac1303ff8791a7e5458646c149753fb1a8652119c73441d7300c725b23
font_01_sfnt_off00013451.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13451 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014c68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14C68 11268 bytes
SHA-256: a6c23266fbea5437393d3f5cdf9b25dec8846873580c1a74dd800473efff2bdd