Malicious PDF — malware analysis report

Static analysis result for SHA-256 1efb1b6740f463d3…

MALICIOUS

PDF

71.5 KB Created: 2021-09-04 14:17:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 19725ee1c46dec54a2beef8c1b0354e2 SHA-1: 6914981f0b41a8f318d8e43936b5c6e05eb88cbb SHA-256: 1efb1b6740f463d385ccd62be36007f3ade76365da825911d837b14cde59d459
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many of which are hosted on compromised CMS uploads or disposable domains, suggesting a link farm or phishing lure. The presence of embedded URLs and the PDF structure point towards an attempt to redirect users to malicious content, likely for credential harvesting or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://festival.bg/fckeditorfiles/file/zanorumirotovug.pdf In PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/769b3ac61e92fd4a0953e22427a51808/sagifamobimesolatatekef.pdfIn PDF document text
    • http://eunlocker.com/Images/Editor/file/96851791912.pdfIn PDF document text
    • http://www.fan-consultants.com.tw/ezadmin/ckfinder/userfiles/files/dulanijafibozenoret.pdfIn PDF document text
    • https://janeunchained.com/wp-content/plugins/super-forms/uploads/php/files/n20l3qt3ij95vf89e3a930n32s/gavubuzexidawarike.pdfIn PDF document text
    • http://mousike.it/img_ins/files/67963157273.pdfIn PDF document text
    • http://modero.vn/upload/files/sinum.pdfIn PDF document text
    • http://rufullthrottle.com/wp-content/plugins/formcraft/file-upload/server/content/files/160881f02b335f---54013958573.pdfIn PDF document text
    • http://lonerangerfanclub.com/ckfinder/userfiles/files/60341089546.pdfIn PDF document text
    • http://eia-edu.com/userfiles/file/vuboti.pdfIn PDF document text
    • https://www.stjohnhomelessshelter.org/wp-content/plugins/super-forms/uploads/php/files/8debd4bc2628c7577193b9035319f678/84644562026.pdfIn PDF document text
    • https://hogies.com/includes/template/uploads/file/91713342315.pdfIn PDF document text
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/4c5fffca7cad5fc2e9a61c0140841977/73790032080.pdfIn PDF document text
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/160833672e3f20---zevebulujunoritudekupati.pdfIn PDF document text
    • http://kino-profi.com/wp-content/plugins/super-forms/uploads/php/files/672ddd785b692cd71a8df1f1b641dbf8/tepejesurujojuzupupi.pdfIn PDF document text
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cfab805e44---jibigorezikumogutimulumav.pdfIn PDF document text
    • http://aircond.md/upload_fck/file/53428230211.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab650535459---72325974971.pdfIn PDF document text
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc63d6a337---mepam.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1612a2f8bc990b---85136250477.pdfIn PDF document text
    • https://artasedanasingaraja.com/uploadfck/file/tozifawexo.pdfIn PDF document text
    • https://lynnesnaturaltreats.com.au/wp-content/plugins/super-forms/uploads/php/files/fb3f3d015a91f93a48debefa14fcfb22/91563903980.pdfIn PDF document text
    • http://tecsun-moscow.ru/docs/file/vopenumizadobevagasuve.pdfIn PDF document text
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073b62356d28---wuleluxerazax.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=6th+grade+math+problems+with+answers+pdfPDF 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_off0000b80e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB80E 11244 bytes
SHA-256: 584d1d179a53e831573ecdb9722f876ec3f90cabc96f43a0263b3799eff3d6e4
font_01_sfnt_off0000d1dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1DD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e9ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9EF 15128 bytes
SHA-256: 11b7574fa754cee5a5e3bf4f684ab3430d2c35a18babf859ef8ea7b14a8bbc34