Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8b35458a637f797…

MALICIOUS

PDF

78.8 KB Created: 2021-10-07 01:10:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 4e9a5fa53eb849867c17b4d74fabd44a SHA-1: 15dab4f863c64924c43a093ac5c468d8bf034e5e SHA-256: b8b35458a637f7972f017d0d5a2384256eff15db0fdf33f5537f56836590c4a2
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed for phishing or malware distribution. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://infrive.ru/uplcv?utm_term=the+coddling+of+the+american+mind+espa%C3%B1ol+pdf PDF link annotation
    • http://acsalma.hu/userfiles/files/dapebopesokimarerinixo.pdfIn PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/16153ca1b8bb87---bujegepevanosasebine.pdfIn PDF document text
    • http://giovanninociti.com/userfiles/files/xesiwugujijiganum.pdfIn PDF document text
    • http://box8websites.com/ckfinder/userfiles/files/65390289960.pdfIn PDF document text
    • http://exito-opakowania.pl/userfiles/file/jagenuriza.pdfIn PDF document text
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16153990d6c81e---4572088698.pdfIn PDF document text
    • http://cerrutistudio.eu/userfiles/files/gewoxabokeruxulavuf.pdfIn PDF document text
    • http://bulmarconsult.com/files/81022116453.pdfIn PDF document text
    • http://premiumdrinks.eu/userfiles/wevazuginegike.pdfIn PDF document text
    • http://biplano.eu/userfiles/files/72806210919.pdfIn PDF document text
    • https://blsautomation.com/ckfinder/userfiles/files/45308665924.pdfIn PDF document text
    • http://xn--80aaaghhaztbcd1agjgbccsgfftf.xn--p1ai/pict/file/ratisugizugasabaxibad.pdfIn PDF document text
    • https://equator-maritime.com/userfiles/file/budupofikutuzipupitu.pdfIn PDF document text
    • https://www.phoenixdentalacademy.co.uk/wp-content/plugins/super-forms/uploads/php/files/3589c4088cfc8401dacbfd9f8fc5f1f0/goxitezalimum.pdfIn PDF document text
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ec7ee23878---sagawisugarariduwoge.pdfIn PDF document text
    • https://www.tonygssoulfood.com/wp-content/plugins/super-forms/uploads/php/files/1a583f23842b1981716c3def0fe6ce14/72692518338.pdfIn PDF document text
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/929dbe950690738e7805d8a03b2a886d/30813298370.pdfIn PDF document text
    • https://stijsr.com/userfiles/file/rikedolekukuzudi.pdfIn PDF document text
    • https://medtek.vn/storage/file/32875286009.pdfIn PDF document text
    • https://attackworkoutprogram.com/app/webroot/files/ckfinder/userfiles/files/xulezifavopawupoderize.pdfIn PDF document text
    • http://alphamarino.kz/images/news/file/goremikekirivaxala.pdfIn PDF document text
    • http://3qbuy.com/CKEdit/upload/files/bajakubafowileganifudefam.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_off0000cbc2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBC2 11236 bytes
SHA-256: ac55f2a349b3fe2b616464c927d3ee4668bd90e849d78be572d31c3926bef775
font_01_sfnt_off0000e572.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE572 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fd84.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD84 17840 bytes
SHA-256: 9a525c4d7105a7bf61300a1d8f427fff6b982c74246219efd7e7be302fdc948c