Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f8c183aba5c0b59…

MALICIOUS

PDF

73.7 KB Created: 2021-06-04 19:24:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: 3ce323382e85dd4a8a2e3be68a4464fb SHA-1: 335bc97a96ab9e4d9fdc109da8f055148ad6892d SHA-256: 5f8c183aba5c0b592012690ddb0ded3ccb32a33b8b60b8848360573dde9d9d04
156 Risk Score

Malware Insights

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

This PDF file is identified as malicious by ML classifiers and ClamAV, indicating it's a phishing or trojan delivery mechanism. The document contains numerous links, many pointing to compromised CMS upload directories, suggesting it's part of a link farm designed to distribute malware. The primary lure appears to be offering free book downloads, a common social engineering tactic.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://huntic.ru/uplcv?utm_term=agricultural+economics+books+pdf+free+download PDF link annotation
    • https://www.waterlooarmsnewforest.co.uk/wp-content/plugins/super-forms/uploads/php/files/e257a5f24f1a677f28be45a92b55f56a/45166314412.pdfIn PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/16070587f97901---40541347925.pdfIn PDF document text
    • https://akproauto.com/nbloom/fckuploads/file/bevex.pdfIn PDF document text
    • https://howardsteeves.com/wp-content/plugins/super-forms/uploads/php/files/677e64db6bf080a684126731143fd9b3/18546240393.pdfIn PDF document text
    • http://esipro.fr/userfiles/file/wijulatorekada.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/qi8l3mn2h6clei9gp2fs3lutq9/noberuk.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607bd5585f9b6---buserarufase.pdfIn PDF document text
    • http://ifa-astrologie.de/userfiles/file/tododiferigazijonegowogup.pdfIn PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/160799627d5fc8---44202509139.pdfIn PDF document text
    • http://banlinhkienlaptop.com/userfiles/file/76031841970.pdfIn PDF document text
    • https://webfox.net.au/wp-content/plugins/super-forms/uploads/php/files/3a901a8683dd1e1e9a34ac40b96262ae/gitatiwawurevow.pdfIn PDF document text
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c91f596ab1---15566542707.pdfIn PDF document text
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c8fd34a107---98040795744.pdfIn PDF document text
    • https://g3az.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607271d723970---76018095068.pdfIn PDF document text
    • https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/390ck0n0dbfmk6nfst6ola5d7a/tezopasudot.pdfIn PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/fdbd85098437c9580547111490df0efd/55764388694.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d189.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD189 5644 bytes
SHA-256: e061f786a43e7520d5b58d1d19def717f4d430da3cca72965c901048e771740f
font_01_sfnt_off0000e4a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4A8 10760 bytes
SHA-256: 60291ce10a0ab7f9032c4bb0bb2be6609ae7f549817f1d7c937039ed289cadbf
font_02_sfnt_off0001093e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1093E 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34