Malicious PDF — malware analysis report

Static analysis result for SHA-256 57a5f5205828451d…

MALICIOUS

PDF

83.6 KB Created: 2021-09-07 06:03:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: cff8afbec1823689397c0b67035154a5 SHA-1: b1ddfce4cda0a05075cb306a88af907c0e28761a SHA-256: 57a5f5205828451d504dfb72509e08d151f398d70dcb86c11bd1cb2a41486a07
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

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. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://oniceh.ru/uplcv?utm_term=periodontal+dokular+pdf PDF link annotation
    • http://polskienarty.pl/data/aktualnosci_imgs/file/90268159801.pdfIn PDF document text
    • https://weinquartier.at/wp-content/plugins/super-forms/uploads/php/files/3ef3a325146986eb5972d7b48f93d653/powuwumepopij.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/4d856ebaa65aba51d5a0667dbb4c5674/rewuminufare.pdfIn PDF document text
    • https://kabelkyaobuv.sk/editor_uploads/files/mudulivanadi.pdfIn PDF document text
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086ca7312c54---renakisewilamazeka.pdfIn PDF document text
    • http://ipublicity.cz/data/file/wowedurikuduwoje.pdfIn PDF document text
    • https://musikkursus.dk/userfiles/file/98050835099.pdfIn PDF document text
    • https://pluviaterra.mx/wp-content/plugins/super-forms/uploads/php/files/e93a1938ee821b494d7e4ab344b116ad/61781036083.pdfIn PDF document text
    • http://newkontakt.ru/userfiles/images/file/xexexezete.pdfIn PDF document text
    • https://thejinglelab.com/wp-content/plugins/super-forms/uploads/php/files/7t95127fve6i6k26o4d0sb4iqb/19259926296.pdfIn PDF document text
    • https://dorfadvertising.com/ckfinder/userfiles/files/75815737026.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160ad476cbb6ed---24653269506.pdfIn PDF document text
    • https://personalloan2u.com/wp-content/plugins/super-forms/uploads/php/files/a768ab674719dbff6b8eff9ce2a8d661/rosalemaxumaxivuri.pdfIn PDF document text
    • http://clean-ecology.com/Upload/files/nisulebenukedapanew.pdfIn PDF document text
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7ddbf15a08---77762130866.pdfIn PDF document text
    • http://movementlab.dk/userfiles/file/3551799785.pdfIn PDF document text
    • https://relans-nn.ru/images/docs/file/52245636372.pdfIn PDF document text
    • http://cassotech.nl/site/data/ws/files/wovod.pdfIn PDF document text
    • https://tucsonhomewindowtint.com/wp-content/plugins/super-forms/uploads/php/files/5b470912117f1fe00a1f560af5ce92c9/wufenesomirizemotode.pdfIn PDF document text
    • http://artside.org/data/temp/file/43072034767.pdfIn PDF document text
    • http://mueblesdepladur.es/1/userfiles/file/89198363312.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_off0000e008.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE008 18348 bytes
SHA-256: aea4661f4c449e74c7d98c7ece542faf48e1ce22d1dcdb192c5e6cace44da36d
font_01_sfnt_off00010f6d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F6D 10516 bytes
SHA-256: 9f3892c74c781c7a3ff5601c1ac5a0691190bf5aef5a0bd2d6b4796b3dc13b0f
font_02_sfnt_off00012772.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12772 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1