Malicious PDF — malware analysis report

Static analysis result for SHA-256 e87269e16a9ab681…

MALICIOUS

PDF

73.7 KB Created: 2021-09-09 12:54:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 9d23403d9e6965a993f7ea6227ada2f2 SHA-1: 1b1e102c61d4c5989b294c232db95c80924b35a6 SHA-256: e87269e16a9ab681688d4a97ee27373f6bce96ea14ba60234854118dc516efd2
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm for SEO manipulation or to distribute further payloads. The ML classifier strongly indicated maliciousness, and the structure aligns with techniques used to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • 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://catamma.ru/uplcv?utm_term=where+can+i+watch+coyote+ugly PDF link annotation
    • http://assisdrive.pt/userfiles/file/70213114629.pdfIn PDF document text
    • https://upbfassadenbau.com/upload/file/sipum.pdfIn PDF document text
    • http://koutingchina.com/upload/files/bulanopekokoretixur.pdfIn PDF document text
    • http://computer-rudolstadt.de/upload/file/tikodak.pdfIn PDF document text
    • http://mientaytourist.com/uploads/files/82484209948.pdfIn PDF document text
    • http://duhochoangthanh.com/upload/files/zogevopirovadopo.pdfIn PDF document text
    • http://benhvienlaptop.biz/userfiles/file/ninolomupeto.pdfIn PDF document text
    • https://www.wizzfizz.com.au/application/third_party/ckfinder/userfiles/files/33684952494.pdfIn PDF document text
    • http://lamekatus.com/uploads/ckeditor/files/61717175752.pdfIn PDF document text
    • http://hyunshin.net/userfiles/file/woxusi.pdfIn PDF document text
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/161374339f3200---xetenefesowugo.pdfIn PDF document text
    • http://pizzeriadevita.it/userfiles/files/mopapukapaguned.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134736b1d667---mifelekomukexokavutinu.pdfIn PDF document text
    • http://sjhrz.com/images/upload/File/12483470708.pdfIn PDF document text
    • http://www.barbazan-debat.fr/ckfinder/userfiles/files/metikoronan.pdfIn PDF document text
    • http://heydarbaba.org/resimler/files/dinizejejikojaguwuwinajo.pdfIn PDF document text
    • http://safarang.com/basefile/files/pabiraritinutoxinofugisok.pdfIn PDF document text
    • https://htchninc.com/d/files/wibopakorep.pdfIn PDF document text
    • https://irastuff.com/admin/ckfinder/uploads/files/xibimabulim.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/161381d87a1649---79960371048.pdfIn PDF document text
    • http://engroupe.ca/aym_image/files/mojijijebalape.pdfIn PDF document text
    • http://sakem.org/userfiles/files/63212174856.pdfIn PDF document text
    • http://wagnerpc.com/userfiles/files/lobilesesalunares.pdfIn PDF document text
    • https://yarpaket.ru/userfiles/file/40219173455.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_off0000bdb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDB0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d5c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5C7 10632 bytes
SHA-256: 849da2e25cac92b58b3ad4d1e38d590e867eefbbfe87ef11a8bd8505d932f27a
font_02_sfnt_off0000ee20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE20 16632 bytes
SHA-256: 93c5cccc48a2ca682e5b2bdef00bbcd2ac9021522eee5b7a2c76e7878f3db9bf