Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf3e7efc3c320cb2…

MALICIOUS

PDF

68.8 KB Created: 2021-10-03 02:09:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 9a09dafd7d03d625460bd58fedba2252 SHA-1: 74760a386f66b0968d7c8dc587993c2c477b9ce7 SHA-256: cf3e7efc3c320cb290340428329acaf0bd38a587fd8c2376a9f2bd9f794f2f54
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users. The ML classifier strongly flagged this PDF as malicious. While no scripts were extracted, the structure and embedded links suggest an attempt to lure users to malicious or compromised external sites, likely for phishing or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 http://johnmarzillier.com/ckfinder/userfiles/files/tuxidaxegowa.pdf In PDF document text
    • http://tomaszskiba.com/userfiles/file/54779283334.pdfIn PDF document text
    • https://vibangthuaphatlai.net/uploads/files/90603714208.pdfIn PDF document text
    • http://thainightjob.com/ckfinder/userfiles/files/16396495103.pdfIn PDF document text
    • http://ebiocell.com/uploadfile/file///2021091706384269.pdfIn PDF document text
    • http://bellezaeimagen.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/161322d83e2e81---faxipibebawubaxukegodele.pdfIn PDF document text
    • http://spad.kr/userData/ebizro_board/file/2500538090.pdfIn PDF document text
    • https://salvatoredivilio.it/userfiles/file/ritomutubodesovonipagalov.pdfIn PDF document text
    • http://dmkert.hu/files/file/44157809713.pdfIn PDF document text
    • http://express-service-auto.fr/ckeditor/ckfinder/userfiles/files/gozoloxukazasavoziker.pdfIn PDF document text
    • http://grotech.in/userfiles/file/galubesunedasutuligi.pdfIn PDF document text
    • https://ezsprinting.com/userfiles/file/33916497332.pdfIn PDF document text
    • http://studiolegalezullo.eu/userfiles/files/koxanurexibajom.pdfIn PDF document text
    • http://bctlorraine.org/userfiles/file/92217773341.pdfIn PDF document text
    • http://nsmpublicschool.org/slbdavbatala/userfiles/file/letedevevup.pdfIn PDF document text
    • https://techinnsrl.com/writable/public/userfiles/file/55905368063.pdfIn PDF document text
    • http://dar-tom.pl/userfiles/file/zovutijamat.pdfIn PDF document text
    • https://f1com.ge/wp-content/plugins/super-forms/uploads/php/files/d1dce935a686b8328eb1ad3064fac042/90847129387.pdfIn PDF document text
    • http://pure-chiral.com/upload/files/28100834381.pdfIn PDF document text
    • http://jinruily.com/UploadFile/file/20210906080653980.pdfIn PDF document text
    • http://www.nena-artspace.com/ckfinder/userfiles/files/vikegatanipuw.pdfIn PDF document text
    • https://www.bnbtravels.com/ckfinder/userfiles/files/91543539808.pdfIn PDF document text
    • http://tsnpharma.com/upload/files/fovifolumadugafujabasab.pdfIn PDF document text
    • http://labradory.pl/file/jolazadutorudakirezese.pdfIn PDF document text
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612eee4b4c76f---72443782860.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=overtime+double+payPDF 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_off0000afb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFB1 15096 bytes
SHA-256: 58377df084c60b53ca0a82ac6984ed74c23e4cc458e3fdbe0bd6d20bfdc407c0
font_01_sfnt_off0000d55a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD55A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ed71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED71 10724 bytes
SHA-256: 7a4dbe106a88196d73de4972c0ade05ff45b7b1b9f07205c5cf792a96c91105e