Malicious PDF — malware analysis report

Static analysis result for SHA-256 37353383a4a2f26b…

MALICIOUS

PDF

91.4 KB Created: 2021-06-29 12:47:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: b171ecf31527dbcab0426f2067eeda96 SHA-1: cd0190da253a655c3fcb8b25a83d14c93daed779 SHA-256: 37353383a4a2f26bf6c2195fc0f7db9e5d55e1b729caab24167e593d35db7e3a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to lead users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. While no scripts were directly extracted, the PDF structure and URL patterns are consistent with techniques used to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://lotteppta.com/beta/assets/file/93262148412.pdf In PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2d0d38cea2---morikexasemafetofux.pdfIn PDF document text
    • https://sieuviet.net/webroot/img/files/14547518831.pdfIn PDF document text
    • https://www.elitelawnsolutions.co.uk/wp-content/plugins/super-forms/uploads/php/files/6ern59691jhv5qpprhq9kvu40k/bitupiriv.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/0ecbf1f3c5b98b9f583b030128ecde46/82474635502.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3e222b21b7---43409470763.pdfIn PDF document text
    • http://nhasachconggiao.com/luutru/files/pizagid.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160c0cf1190597---zanowufo.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/4980f1aeccfd144db090f3a85b9bcc6f/57842920110.pdfIn PDF document text
    • https://oilbasaro.com/web/images/ckfinder/files/20210614093101.pdfIn PDF document text
    • https://www.cpro.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16070b913910ee---vomegopelorevitufod.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c936ee745a---muwonogidugaputopimafugi.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cee8db067b3---gozojajudulurani.pdfIn PDF document text
    • https://zivotzaokny.eu/res/file/nunuzaxena.pdfIn PDF document text
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16071fb1cd8b17---devafu.pdfIn PDF document text
    • https://amenajarisiconstructii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608eb498ad049---dimokorusetakinadadu.pdfIn PDF document text
    • http://ankurgroups.com/userfiles/file/80583616573.pdfIn PDF document text
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/gv261cs2fdedf14l65ukn1tepm/xidojosenivugapiza.pdfIn PDF document text
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/160caff1509db4---lojikorokan.pdfIn PDF document text
    • http://rauvuonsach.com/images/uploads/files/tafago.pdfIn PDF document text
    • http://anbao.vn/uploads/userfiles/file/61807288502.pdfIn PDF document text
    • http://wypelnienia.kratex.pl/wp-content/plugins/super-forms/uploads/php/files/c91a11711fc0f4b20b708270524cb71b/fosivuduwafeladuwud.pdfIn PDF document text
    • https://www.ideaklinikbakirkoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ef69084abc---76663322552.pdfIn PDF document text
    • http://www.asap-recruitment.net/upload/file/11136345878.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=short+story+with+comprehension+questions+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_off0001031b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1031B 16672 bytes
SHA-256: a7f8e467172e9fd6e430b4e40f274397ce5948b2d0b83a207037507961ab8ba1
font_01_sfnt_off00012e36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E36 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001464d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1464D 11200 bytes
SHA-256: 02009068f20ae67298f8a661829dec5c0e939d4649555acc64e32e34d6ee1e6b