Malicious PDF — malware analysis report

Static analysis result for SHA-256 e56f1a817834f89e…

MALICIOUS

PDF

80.1 KB Created: 2021-09-03 04:00:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 95e85abbaa7b17428cb69dba74ce0373 SHA-1: d80c8f97e135fbe27f658322dc109410951b3be4 SHA-256: e56f1a817834f89e74d5414bdccfab083bd02d9b42dedb05ace1a98db86591fc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of embedded URLs, many of which point to external PDF files hosted on various domains. Heuristics indicate this is a link farm on disposable or compromised hosting, and ClamAV detected it as a phishing trojan. The ML classifier also strongly flagged it as malicious. The primary attack pattern involves luring users to click these links, likely leading to further malicious content or phishing attempts.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://detectiveoffice.net/userfiles/file/dugowapoferogituxitologem.pdf In PDF document text
    • http://moveworldtogether.com/datas/files/jefowitarekomalatirakig.pdfIn PDF document text
    • http://sushimura1.com/uploads/files/wapuwezivuzufepi.pdfIn PDF document text
    • https://cbdc.co/uploads/ckfinder/userfiles/files/84697750217.pdfIn PDF document text
    • http://dajuicebarus.com/uploads/files/27312782461.pdfIn PDF document text
    • http://hoshitorionline.com/uploads/files/jazerupexexuluzu.pdfIn PDF document text
    • http://korvet-sp.ru/userfiles/file/vezujobejamigerowu.pdfIn PDF document text
    • http://zaiger.ru/img/file/bebuku.pdfIn PDF document text
    • https://aviseco.ro/userfiles/file/7052846076.pdfIn PDF document text
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/346721ca2ea2b47702806d9ab4f1d3ab/20291071986.pdfIn PDF document text
    • http://delannahotel.com/user_img/file/larorowofomij.pdfIn PDF document text
    • https://amblamy.ee/upload/file/tomeziwinoso.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bd3f0973c9---43467819361.pdfIn PDF document text
    • http://rotang.net/userfiles/file/munagogoredukave.pdfIn PDF document text
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096b53d0c35d---zeruwasapefagasotutixogu.pdfIn PDF document text
    • https://relans-nn.ru/images/docs/file/18122011285.pdfIn PDF document text
    • http://angeladaniel.eu/uploads/files/58836345216.pdfIn PDF document text
    • https://awlights.com/wp-content/plugins/super-forms/uploads/php/files/eaddd85cafa1ba73e6e3a444726fa694/27174922671.pdfIn PDF document text
    • http://becucci.it/userfiles/files/lolemesotafu.pdfIn PDF document text
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607c2437bbfd0---13359573902.pdfIn PDF document text
    • https://avukatwebsitesi.trakyasoft.com/upload/files/15678661569.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=sequences+nth+term+worksheetPDF 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_off0000d1c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1C7 18620 bytes
SHA-256: 0f499c9a5827b2c29d99c92a993493289e7ccceef9bb2ab708993aad6f636277
font_01_sfnt_off00010224.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10224 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011a3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A3B 10696 bytes
SHA-256: e12778e3ab4f0c87b9532fd9d43b7206fbe54bfdc5649acc0f599653e13fe7ab