Malicious PDF — malware analysis report

Static analysis result for SHA-256 2556c4d389bf52a8…

MALICIOUS

PDF

84.9 KB Created: 2021-06-30 05:54:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 8dd633636f49521b3130ca7600714702 SHA-1: 46a8bc10c3e05d27a9fb04a81daf0d941d70da06 SHA-256: 2556c4d389bf52a8540c25074f323a7a259ca09fbdeed0712140270a1fc59508
156 Risk Score

Malware Insights

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

The PDF contains numerous external URIs and link farm heuristics, indicating its primary purpose is to redirect users to other sites. Several of these links point to compromised CMS upload storage, suggesting a tactic to host malicious content or obscure the true destination. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://angelescare.com/userfiles/file/tijujel.pdf In PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091d215d559a---gekovaxekasa.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/72b9c364da4f71251e4828f47af0d95d/xozaleju.pdfIn PDF document text
    • http://bagandpack.ru/wp-content/plugins/super-forms/uploads/php/files/cd70414df44c96846619aac76e64f9ea/11059055235.pdfIn PDF document text
    • https://desertflying.club/wp-content/plugins/formcraft/file-upload/server/content/files/1606c908bc9c08---30680391684.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0a42fcbf82---pobefetemodolujavo.pdfIn PDF document text
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072348579676---kixoniveguxa.pdfIn PDF document text
    • http://skipjackpoke.com/ckfinder/userfiles/files/98083435192.pdfIn PDF document text
    • http://faradtvandor.hu/picture/userfiles/file/xoxej.pdfIn PDF document text
    • http://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16071b7f74b39c---latilov.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/3d95213085fc9068ba6efa245f5cb7ea/fumabekovetukawazizaf.pdfIn PDF document text
    • http://ozona.pt/wysiwygfiles/file/nezezoxofuturozod.pdfIn PDF document text
    • http://austria-ex.com/images/blog//file/sijetudalaxorenozov.pdfIn PDF document text
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607f065331e60---38355636131.pdfIn PDF document text
    • http://christopherdallo.com/file/zakapopuvovulo.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e7ff69024e---kaxagugowuz.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd6a6c55726---10395810678.pdfIn PDF document text
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4df3ca6e38---dololikitimalaralunijabid.pdfIn PDF document text
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/574ad666d0cbc298646a58968266d4fd/fobapezolitulerulik.pdfIn PDF document text
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/92531179a384ddb27b8dd708993d1f99/zirenotodazadorekij.pdfIn PDF document text
    • https://alkirbilaw.com/userfiles/files/pevutolunipug.pdfIn PDF document text
    • https://esperanzadeavila.com/fotos/file/12292622827.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=there+is+need+synonymPDF 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_off0000eb3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB3A 17140 bytes
SHA-256: d38a3bc2293af22ffb53e19697f269b5c0524c27dfc949bd98b31dfadd3a0f4b
font_01_sfnt_off000117ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117AB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012fc2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12FC2 10284 bytes
SHA-256: 5a7b6bf2173d458d0834f3908e1b6bca4ea61e03fe5aee0282c5dc5464d60d42