Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5a7a78a94eb9549…

MALICIOUS

PDF

80.3 KB Created: 2021-09-13 20:15:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 7f0855f6390f7d8943d1f7250ef4101e SHA-1: 9de1a22d1f5b2fd6edaa75590b69c8b79f81944b SHA-256: b5a7a78a94eb95497f69ee8aedeb7802a7e08ed728db04268c5364b1c8aa68b2
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised CMS upload directories or are hosted on disposable domains, indicating a link farm designed to redirect users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://www.prieur-equipement.com/ckfinder/userfiles/files/61169390992.pdf In PDF document text
    • http://weighlessthisyear.com/ckfinder/userfiles/files/xuluvubudaxevisotafi.pdfIn PDF document text
    • http://xn--80aaae7amexjfdlfdfg.xn--p1ai/files/file/17643755377.pdfIn PDF document text
    • http://otestmanager.org/club/data/userfiles/file/20210912014500.pdfIn PDF document text
    • https://polresseluma.com/assets/ckfinder/core/connector/php/uploads/files/14372473742.pdfIn PDF document text
    • http://tyros-club.de/userfiles/file/23363322436.pdfIn PDF document text
    • http://pomocnaukowa.net/Upload/file/fisiw.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161312a0b95fe5---zujavajixutufumekewe.pdfIn PDF document text
    • https://piauiaqui.com/ckfinder/files/78157382978.pdfIn PDF document text
    • http://autoscuolavalerio.it/userfiles/files/panumerefa.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/161311e78bd49a---fopajoka.pdfIn PDF document text
    • http://wickedcheesy.com/images/file/nutive.pdfIn PDF document text
    • https://aqua2go.pl/galeria/file/44715718077.pdfIn PDF document text
    • http://shopcloud.cloud/ckfinder/userfiles/files/liluwun.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/88700937021.pdfIn PDF document text
    • http://gruaszarate.com/ckfinder/userfiles/files/31987526670.pdfIn PDF document text
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/61ac25e4d5b99e4c19894763d3974162/rebizajiwosevamogazemivo.pdfIn PDF document text
    • https://tsegypt.com/file/97123585650.pdfIn PDF document text
    • http://huntland.hu/upload/file/54264285613.pdfIn PDF document text
    • http://kryotherapie.net/neu/userfiles/file/91548168644.pdfIn PDF document text
    • https://partetesal.ir/data/file/68761483212.pdfIn PDF document text
    • http://club-integra.ru/userfiles/file/80527960559.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cb6d89b222---dorosexulogurujer.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=tiktok+downloader+apk+modPDF 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_off0000d6b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6B2 17516 bytes
SHA-256: 4a4015393e37a52bfc971a76d278f0cafdf73cdb294a268f3ccb0fff69762bd1
font_01_sfnt_off000103da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103DA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011bf1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BF1 10528 bytes
SHA-256: 3cc2a918cdada9c8ff92a55f86ff8d56250828ff5fbfb59469648e772fca7844