Malicious PDF — malware analysis report

Static analysis result for SHA-256 35a78341d69a5eac…

MALICIOUS

PDF

68.8 KB Created: 2021-09-04 09:06:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: a0406feda462ae9d0a223e48cc7f21ad SHA-1: ef52a55dcfe5e53fc15770d989ced2e7625eea06 SHA-256: 35a78341d69a5eac5bc17aab771613fef3b0c228c07c27f8bfabda03367bf205
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and uses an image-based lure. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 68 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://inwebjor.ru/uplcv?utm_term=pyramidal+and+extrapyramidal+tracts+pdf PDF link annotation
    • http://studiofantino.it/userfiles/files/75122742368.pdfIn PDF document text
    • http://mopi.eu/ckfinder/userfiles/files/45593858972.pdfIn PDF document text
    • https://shinyjewellers.com/wp-content/plugins/super-forms/uploads/php/files/2l1erhb8adt44m3m53sb762kc3/89736351755.pdfIn PDF document text
    • http://bochosushi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607eae8cc4ae9---76689967299.pdfIn PDF document text
    • http://erex.hu/upload/file/senen.pdfIn PDF document text
    • https://megashina24.ru/files/files/42713299143.pdfIn PDF document text
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a46b87f00ea---wopakedazu.pdfIn PDF document text
    • http://bikipvuikhoedep.com/app/webroot/files/editor_upload/files/71898362110.pdfIn PDF document text
    • https://gulfcans.com/home/madarmun/public_html/gulfcans/images/bulk_images/files/2217816953.pdfIn PDF document text
    • http://xn--80aaae7amexjfdlfdfg.xn--p1ai/files/file/76232370863.pdfIn PDF document text
    • https://ols.lighting/wp-content/plugins/super-forms/uploads/php/files/38ac8cdf0004732772ff281ab178d0b7/xojono.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/41031981021.pdfIn PDF document text
    • http://bukharaatlanta.com/sites/default/files/file/zixapisuvikusitebolajabuf.pdfIn PDF document text
    • http://aeronautike.com/userfiles/file/79915928436.pdfIn PDF document text
    • http://beachfirebrands.com/userfiles/file/fajekore.pdfIn PDF document text
    • https://doluhosting.com/calisma2/files/uploads/retitepakole.pdfIn PDF document text
    • http://szao-spb.ru/images/news/file/xagasomilobagosi.pdfIn PDF document text
    • http://giasuthienphuc.com/Images_upload/files/kifoziwo.pdfIn PDF document text
    • http://talleresjpg.es/img/file/80524384474.pdfIn PDF document text
    • https://audreyheselmans.com/_files/file/figeranumopum.pdfIn PDF document text
    • https://aulacvn.com/upload/fck/file/bukomus.pdfIn PDF document text
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/1q2qrf6mmdog0jo7euttu0n7tf/98885244686.pdfIn PDF document text
    • https://moveo-sport.pl/userfiles/file/nuwadujamaliragirufu.pdfIn PDF document text
    • http://ever0036.com/assets/uploads/ckedit/files/20210613113620.pdfIn PDF document text
    • http://munnarinfo.in/userfiles/file/jupadeluzedajige.pdfIn PDF document text
    • 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_off0000b199.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB199 10880 bytes
SHA-256: 63bcde0946b3f15c073ea4b621556bc91be79e12fe7d022f55fda7ca4902b596
font_01_sfnt_off0000cab8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAB8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e2ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2CA 14136 bytes
SHA-256: 5d145fb651af1f981485a3339f74f797bca242a5ad4dfeeddcf6f2c61956f15b