Malicious PDF — malware analysis report

Static analysis result for SHA-256 9838583728217a01…

MALICIOUS

PDF

82.7 KB Created: 2021-06-28 01:54:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: b05628d1b2284564adb0fc92b31ec9fe SHA-1: 34ba18260dc2904ce2c3d1ca4d2524354f82a23a SHA-256: 9838583728217a01d043f149993c398129ba5f7727ddcbcaf5239681890e4210
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. The heuristics reveal it functions as a link farm, directing users to multiple domains, many of which are hosted on compromised WordPress sites or disposable hosting. While no scripts were explicitly extracted, the nature of link farms in PDFs often involves JavaScript to redirect users, suggesting an intent to lead victims to phishing pages or download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://visaonline-vn.com/wp-content/plugins/super-forms/uploads/php/files/t0qg45l1m7qonnavm9te53ou8v/92363308930.pdf In PDF document text
    • http://anhuishangbiao.com/upload_fck/file/2021-5-9/20210509232100177107.pdfIn PDF document text
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607dfb0586d85---wunowasifofera.pdfIn PDF document text
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075161b86397---68836183669.pdfIn PDF document text
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c9e0a05dd52---79516607848.pdfIn PDF document text
    • https://yingzhaoliuart.com/upload/file/23413487960.pdfIn PDF document text
    • https://tirthmobile.com/wp-content/plugins/super-forms/uploads/php/files/n90cg4cn8ko61bkcc34297hdgc/ribazolenuba.pdfIn PDF document text
    • https://urbanplace.me/wp-content/plugins/super-forms/uploads/php/files/72f69b195d5040636d849b33833b400c/41993736962.pdfIn PDF document text
    • https://creativitagh.com/pevron/www/img/file/febozajumokuw.pdfIn PDF document text
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16084e22cac5c6---29458006368.pdfIn PDF document text
    • http://anhuishangbiao.com/upload_fck/file/2021-4-29/20210429110431908285.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/duxuzu.pdfIn PDF document text
    • https://studio45.live/wp-content/plugins/super-forms/uploads/php/files/edq991el6irvb6tbar6bhcerj5/47042178756.pdfIn PDF document text
    • https://comodee.com/wp-content/plugins/formcraft/file-upload/server/content/files/160963a2beac33---19942844827.pdfIn PDF document text
    • https://biomedchita.ru/imeg_master/file/derojivelotimere.pdfIn PDF document text
    • http://thehawthornnyc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094a25b8dae6---vakimozon.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1772b1f42f---25811926193.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1609a947308934---95161760319.pdfIn PDF document text
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c98cb5b9128---rejajivu.pdfIn PDF document text
    • http://proxkimya.com/resimler/files/zurolumejejomemikelazesas.pdfIn PDF document text
    • http://igigeothermal.jp/userfiles/file/sidezolatare.pdfIn PDF document text
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/qbp340tulmpttjnol2q7hebkkl/jogokajupulofumanedurut.pdfIn PDF document text
    • https://afayl.com/userfiles/file/453077593.pdfIn PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/cd13633e3fb50a5f973d9ea7111b7a6a/82827987025.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=manual+process+to+automationPDF 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_off0000e067.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE067 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f87e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF87E 10628 bytes
SHA-256: 6585381032b7e0649984346aeeb6e9a6643d85108bafb13a795316e79c940629
font_02_sfnt_off000110c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110C5 17164 bytes
SHA-256: c7e3a78543f24769f7168b6a1645bb3bbb05700b3a67ea5299eded64726e7ef8