Malicious PDF — malware analysis report

Static analysis result for SHA-256 cc4850cfb4e20805…

MALICIOUS

PDF

95.2 KB Created: 2021-07-01 11:34:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: be2b50dbbd2eabc43a79d10cdd837545 SHA-1: cc6a52b76e527ae060d4f66b6d142a9998626f9d SHA-256: cc4850cfb4e20805cd8874139bb3d518ddcde89c71a1e1f6c08a695100d702c1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised WordPress sites, suggesting a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://laborke.ru/uplcv?utm_term=women+with+short+hair
    • https://seataclightingalaska.com/wp-content/plugins/super-forms/uploads/php/files/f28545e4c23cded537c9cb34ded12012/97310833429.pdf
    • http://vasamo.org/pds/userfiles/files/51946995986.pdf
    • http://vinhthuan.com/upload/files/27798010267.pdf
    • http://www.injamal.es/nueva/ckfinder/userfiles/files/73499707106.pdf
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071dfd88697c---67607004781.pdf
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/16096a05d76478---2220712837.pdf
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/160a0eadcbac66---vulafakos.pdf
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/160b782fd28296---80210105925.pdf
    • https://florerialafloresta.com/ckfinder/userfiles/files/92639853145.pdf
    • https://agrilaui.com/userfiles/file/75181654750.pdf
    • http://easternsheep.by/app/upload/file/rojiponiwarudavopo.pdf
    • https://ewt.cz/res/file/nulupamaxagufojufo.pdf
    • https://quatcongnghieput.com/uploads/files/18546745898.pdf
    • https://arizonapoolcontractor.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088203a8b218---dopajolebonovobab.pdf
    • https://kipass.fr/userfiles/file/80976758480.pdf
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bca5af1d495---69998922262.pdf
    • https://www.kunapak.com/wp-content/plugins/super-forms/uploads/php/files/7iquntjc01cs9qs90kfksbekls/22769140629.pdf
    • http://berrybucs1973.com/clients/3/3a/3a2d6910be1067feaf6dc79f90d505e0/File/ladezonenipus.pdf
    • https://southtours.com/wp-content/plugins/super-forms/uploads/php/files/hih40nqa2su3ek31ejiip1p5qi/69024241146.pdf
    • https://www.criteriainvest.com.br/wp-content/plugins/super-forms/uploads/php/files/19ipa5br08l1vqppame275o5qo/73840667239.pdf
    • http://www.minaakshimajumdar.com/fckimages/file/kujisexumebozagukuzuramib.pdf
    • https://systematix.pl/userfiles/file/talelezonirepop.pdf
    • http://jdhs77.com/clients/58520/File/57268531560.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3049c9bbf0---62082087728.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000115a2.bin
b3f13c198df2c8a48e3ad2b7aa4deda308c30b8540fa6545d1b0d181232d080e
pdf-font-stream PDF embedded font (sfnt) at offset 0x115A2 10408 bytes
font_01_sfnt_off00012d10.bin
30c46cd95a9b29bfd52b6a945ecf794200ff052e60fc3df1ea76765b7b66c688
pdf-font-stream PDF embedded font (sfnt) at offset 0x12D10 16376 bytes
font_02_sfnt_off0001578d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1578D 16792 bytes