Malicious PDF — malware analysis report

Static analysis result for SHA-256 0c6d76b81882fbbf…

MALICIOUS

PDF

82.5 KB Created: 2021-08-28 13:11:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e494a90e597f68a968c4c9bdd845c423 SHA-1: 5bcd6d8bef763ba65585667160c366ae8108b39c SHA-256: 0c6d76b81882fbbf1c2409b41e40a0c6c8138b81bd77a83b3046d926812a42e6
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for exploiting PDF vulnerabilities. Heuristics indicate the PDF acts as a link farm pointing to compromised WordPress upload storage, suggesting it's designed to host malicious files or redirect users to phishing sites. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://bentzendesign.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607ef4098103c---45864425378.pdf
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607396069d087---kibokuvizifo.pdf
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/pe0st47ukjcd223ojs4ijp33q8/44634318306.pdf
    • https://paeonia.ch/userfiles/files/87484153948.pdf
    • http://bike-aholic.com/UserFiles/file/rowogapo.pdf
    • http://www.biotanika.pl/upload/file/minufaviwusegenof.pdf
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160863e7d63bd6---mafojuwakewiwezevivabuv.pdf
    • http://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608cc5b8e471f---67530876168.pdf
    • http://giasudaihocsupham.com/Images_upload/files/96196473055.pdf
    • http://nassagroup.org/app/webroot/js/ckfinder/userfiles/files/wewowuse.pdf
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a447cc541f9---13432500164.pdf
    • http://banghetretunhien.com/media/ftp/file/xewojiwaxon.pdf
    • https://anyimaker.com/upload/users/files/5172465258.pdf
    • https://sportsht.com/userfiles/file/72040468815.pdf
    • https://emmaushuis.org/pages/kitefupesifotuv.pdf
    • http://www.web-globus.de/ckfinder/userfiles/files/42204136817.pdf
    • https://vuaship.com/wp-content/plugins/super-forms/uploads/php/files/6l4fnq3d16uk9gpgk8gklu1bpf/buwosupoluwi.pdf
    • http://tc-antey.ru/uploads/files/mujamajabuge.pdf
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a44ac53497a---pigedigoxaj.pdf
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/p9hb40jubhaid89eftq77k9403/riwuriwepeko.pdf
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4bda3147c9---9293491287.pdf
    • http://fermobkorea.com/userfiles/file/20210811193140.pdf
    • http://119pump.net/d/files/97823077464.pdf
    • http://wwpokebar.com/uploads/files/banefizebizumulafosibi.pdf
    • https://lanjutpt1.com/contents/files/69580228329.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=look+so+perfect+standing+there+in+my+american+apparel+underwear
    • 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_off0000d632.bin
801a3bdf428bd90034c9c36768d1e8324634fc743e4f8853e7bc706c7d4aacca
pdf-font-stream PDF embedded font (sfnt) at offset 0xD632 19424 bytes
font_01_sfnt_off00010851.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10851 16792 bytes
font_02_sfnt_off00012068.bin
8bb71a5e61d8c8b48d953b7288803e00a08fc03cc7258c872bcb8080f7cb739d
pdf-font-stream PDF embedded font (sfnt) at offset 0x12068 11416 bytes