Malicious PDF — malware analysis report

Static analysis result for SHA-256 4bd6a191933c7af2…

MALICIOUS

PDF

86.0 KB Created: 2021-07-02 22:22:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: a3e97e5209972d2528ba8beb57ad97bf SHA-1: 844351526a1f80743fdf18acb96b76fa0b5cbbb6 SHA-256: 4bd6a191933c7af2101f70ba4a35b0a9718ebbfc06ed53df67319440c98c740f
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many of which point to compromised WordPress sites hosting other PDFs. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution through these link farms. The document body is unreadable, but the heuristic firings clearly identify the link farm and compromised hosting pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9848

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://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160705bd9d3867---85068300090.pdf In PDF document text
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a80816dc3ea---46260664353.pdfIn PDF document text
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0b576536a5---degexi.pdfIn PDF document text
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/3o2frle8gedreji8utb5ag9klc/kolixugekezusexeneruta.pdfIn PDF document text
    • https://assurancemauricie.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ec563421a1---vagedi.pdfIn PDF document text
    • https://legacyltg.com/wp-content/plugins/super-forms/uploads/php/files/ff09c70b28b3a9ffb46f38e043f41783/xoxogilaxifajopize.pdfIn PDF document text
    • http://www.airportlimofortlauderdale.net/wp-content/plugins/formcraft/file-upload/server/content/files/16084eb8784689---65899495076.pdfIn PDF document text
    • http://christschoolblr.in/userfiles/file/71612351660.pdfIn PDF document text
    • http://thanuyentea.com/ckfinder/userfiles/files/gakejedutazetuzosudubim.pdfIn PDF document text
    • http://kythuatviet.vn/uploads/userfiles/file/90071542104.pdfIn PDF document text
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c42b2d88df0---xizutujixo.pdfIn PDF document text
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/ikl4pdea08237bb899mhks8046/nadojejim.pdfIn PDF document text
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8300598f85---kaxejekonut.pdfIn PDF document text
    • https://mimpishio2.net/contents//files/53456319099.pdfIn PDF document text
    • https://actor-conseil.com/files/file/fumobalamixakebolitekafo.pdfIn PDF document text
    • http://bradleyhillsapartments.com/demo/uploads/contents/file/21828977510.pdfIn PDF document text
    • https://ntwbearing.com/UserFiles/File/gelomudasuzafit.pdfIn PDF document text
    • http://shreyaghoshal.com/konadnew/userfiles/file/40773107803.pdfIn PDF document text
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160999fc3b53d4---kijekenalavo.pdfIn PDF document text
    • https://www.indoorclub-informa.com/boletines/img/file/94826059155.pdfIn PDF document text
    • https://dixietemporarystorage.com/wp-content/plugins/super-forms/uploads/php/files/78ed2eee7f3b5623bbb968f6a819f960/bifexetan.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608a09bf11ec7---64836644367.pdfIn PDF document text
    • https://parisautotravel.com/wp-content/plugins/super-forms/uploads/php/files/o7ev0964smh5mjv6oc6lsm9bl5/vupumozutokitaxojomu.pdfIn PDF document text
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6cbf6734b1---95960066235.pdfIn PDF document text
    • http://leebyunghun.org/new/upload/board/files/15027799154.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160880571f0283---2267801764.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=scare+the+bejesusPDF 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_off0000ea60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA60 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010272.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10272 18552 bytes
SHA-256: 3f6c151a0daabfa5f013508e39e0ce21bd86f1f4295f452f404b9bad77843351
font_02_sfnt_off00013305.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13305 10408 bytes
SHA-256: 21d71eeff1d8b28a511e1c916706eb86d4e13c0e3957465992906ae4a050b6c1