Malicious PDF — malware analysis report

Static analysis result for SHA-256 d578ed9fb26b4382…

MALICIOUS

PDF

78.6 KB Created: 2021-09-12 10:10:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 837db3c1354041be9ea38003bef91de8 SHA-1: de35ad5596a13ba296dd4376417298704f10b505 SHA-256: d578ed9fb26b4382db043cb7835c594f7118360c7c14d9d2a6905465b4fc50eb
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 compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or SEO spam. The document body is unreadable, but the heuristic firings and URL analysis are sufficient to determine the attack pattern.

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 http://webcertain.asia/contentupload/fckeditorUploads/organization_/file/85445362874.pdf In PDF document text
    • http://duocmyphamcongty.com/app/webroot/uploads/files/sitexoxazuribok.pdfIn PDF document text
    • https://hankilfood.com/upfile/files/54865882128.pdfIn PDF document text
    • http://enjoyisagenix.com/ckfinder/userfiles/files/tuzipejuwebotib.pdfIn PDF document text
    • http://poexali.org/static/image/_u/system/files/81388476769.pdfIn PDF document text
    • http://pampa.be/uploads/userfiles/files/baretekimadinizazutaxowit.pdfIn PDF document text
    • http://rotarycochinharbour.org/ci/userfiles/files/49442636748.pdfIn PDF document text
    • http://lachina.cn/upload/file/vitowasup.pdfIn PDF document text
    • https://postelezmasivu-ostrava.cz/ckfinder/userfiles/files/14702248931.pdfIn PDF document text
    • https://grandplaza.bg/uploads/assets/file/56211683631.pdfIn PDF document text
    • https://menu2uplus.com/images/file/23142785842.pdfIn PDF document text
    • https://loffoxfitness.mvwebsolution.com/userfiles/files/88776047437.pdfIn PDF document text
    • https://studiecarriere.it/uploads/file/dilis.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/0nrd8pfa1qrdoftbrqrf4hh7i2/zufafog.pdfIn PDF document text
    • https://muzeumkonstancina.pl/attachments/file/44983316878.pdfIn PDF document text
    • http://2safe4u.cz/UserFiles/File/detawotutamolojijal.pdfIn PDF document text
    • https://yukkumpulgroup1.com/contents/files/bulonetopotajejijib.pdfIn PDF document text
    • https://portecitadelle.portecitadelle.ca/ckfinder/userfiles/files/23711819456.pdfIn PDF document text
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/161357b1ce3c1f---vezofu.pdfIn PDF document text
    • https://cylinder96.ru/admin/ckfinder/userfiles/files/lavoza.pdfIn PDF document text
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161319f5388526---bironotobelopugozuneg.pdfIn PDF document text
    • http://saringkarnwood.com/UserFiles/file/sorugetoxuvo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=mar+gaye+o+loko+full+movie+download+720pPDF 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_off0000cb0f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB0F 11316 bytes
SHA-256: e03fe7767208f7f0187618a360a6bae904156047eae53cfab586656961cd177b
font_01_sfnt_off0000e58a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE58A 18172 bytes
SHA-256: 5e97ae583086a2e60c37fa2a42a60cd793c023636a8a88f78849bc25d43c96bb
font_02_sfnt_off00011490.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11490 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1