Malicious PDF — malware analysis report

Static analysis result for SHA-256 34134b7d9fe5ba5d…

MALICIOUS

PDF

85.2 KB Created: 2021-10-08 02:49:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 6428e995e246202acbc9f51eff0c0bdb SHA-1: 784e56ba28c221059bae9bb92ed46b771549491c SHA-256: 34134b7d9fe5ba5d275d4d7647f9d865afb8ff16b2db045d114efb0c7a676dc6
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with several URLs pointing to compromised CMS uploads or disposable hosting, suggesting a phishing or malware distribution scheme. The document body was unreadable, but the presence of numerous external links and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic strongly suggest the document's purpose is to redirect users to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://szyldkj.com/luodan/images/userfiles/file/31368987511.pdf In PDF document text
    • http://k12kos.com/ckfinder/userfiles/files/95105415776.pdfIn PDF document text
    • http://keramann.ru/uploads/files/banevoriseja.pdfIn PDF document text
    • http://hopkim.vn/upload/files/42628187653.pdfIn PDF document text
    • http://skazka76.ru/pic/userfile/51805304197.pdfIn PDF document text
    • https://h16hr15k-h19hr37urn.com/contents/files/28039890378.pdfIn PDF document text
    • https://aakritidigitals.com/userfiles/files/tokasu.pdfIn PDF document text
    • https://getlovebooks.com/wp-content/plugins/super-forms/uploads/php/files/be70f6c0d7b385888189d1684be4ca32/57018806205.pdfIn PDF document text
    • http://www.laterveer-biesenbeek.nl/ckfinder/userfiles/files/54071784733.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615b8dcaa6875---mibuju.pdfIn PDF document text
    • https://copab.tn/216mag.svn/uploads/files/7063560615.pdfIn PDF document text
    • http://yuhuimachinery.com/d/files/27112639441.pdfIn PDF document text
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f435919414---fiduwexotejudiliwoj.pdfIn PDF document text
    • http://ingfrimale.com/userfiles/files/37190096094.pdfIn PDF document text
    • http://staropolski.net/Upload/file/53368811266.pdfIn PDF document text
    • https://shaplaconsulting.com/app/webroot/ckfinder/userfiles/files/jolujaderosozuz.pdfIn PDF document text
    • http://biplano.eu/userfiles/files/napafaliparejexugifuvaraw.pdfIn PDF document text
    • http://hosungtour.com/FileData/ckfinder/files/20210907_A23A7819D78A127F.pdfIn PDF document text
    • https://jxlmedu.com/file/files/20210903_035511.pdfIn PDF document text
    • http://testplanet.nl/uploads/files/danasopadavof.pdfIn PDF document text
    • http://cobmedia.hu/include/vikegimepemanikejafepugi.pdfIn PDF document text
    • https://www.hediyevideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16152965251504---99623506594.pdfIn PDF document text
    • https://alrashed-alsaleh.com/userfiles/files/66333644600.pdfIn PDF document text
    • https://solidpractise.com/files/userfiles/file/66166284837.pdfIn PDF document text
    • http://clinicaveterinariacene.com/userfiles/files/1364563777.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=cto+technical+interview+questions+and+answersPDF 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_off0000e6b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6B2 18360 bytes
SHA-256: 3ca062e24566ba15ed5002ac3969cf373d9243a48c03dc04e3d654af81e77378
font_01_sfnt_off000115d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115D6 10896 bytes
SHA-256: 5b57814ec80659e84c03dbfaca15bfcf4f6c369a000a03bf946d2cb386117933
font_02_sfnt_off00012ee0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12EE0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1