Malicious PDF — malware analysis report

Static analysis result for SHA-256 af5128e3863e939b…

MALICIOUS

PDF

81.0 KB Created: 2021-09-01 00:45:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 826b4c4457a2339690fc3ae2e734e10a SHA-1: 0b43d770f40252431c2118a15b47acd762a01784 SHA-256: af5128e3863e939b6eb65746abe7db83fe4a279b2acda4190349b6b94853db6d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised WordPress upload directories and other disposable hosting, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9944

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://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16092d581a8f53---65830061656.pdf In PDF document text
    • http://www.lugashotel.com/data/editorfile/potajevosenesakozugodetu.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16103cc72daf68---25962068798.pdfIn PDF document text
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/11190531a8274888553ff91270e639f2/busurudemexemadub.pdfIn PDF document text
    • https://officialbacknumber.org/editor_up/sabuwifulerivafefaled.pdfIn PDF document text
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/160aba3739b55e---83676671909.pdfIn PDF document text
    • https://www.c2commercial.com/wp-content/plugins/super-forms/uploads/php/files/138c9829acbfa511cfdebfe94e8d1a88/lunazisekik.pdfIn PDF document text
    • http://zaintik.org/files/galeria/files/37138161993.pdfIn PDF document text
    • http://canoeing.by/pics/files/dovaxurajalufip.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6abc76b214---13279412565.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/160e863837c437---vaxugabopigofoseguka.pdfIn PDF document text
    • http://www.cpnatacao.pt/backoffice/ckfinder/userfiles/files/6220773410.pdfIn PDF document text
    • http://workprohealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093fa16d221c---gatulezagekokuviledovebet.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a476f756fcf---56080154205.pdfIn PDF document text
    • http://jmvlpslimited.com/ci/userfiles/files/nelupubamiwetovuwopamev.pdfIn PDF document text
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609f846ea1bbd---zukukazozerikazewim.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1606d53015572d---mimolabowaguxoxawobezareg.pdfIn PDF document text
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ee5aa6cfea3---6950259254.pdfIn PDF document text
    • http://saydersan.com/firma/files/54097335052.pdfIn PDF document text
    • https://pharma-tools.eu/galeria/file/xubiroroluga.pdfIn PDF document text
    • http://bioterapiazabiegi.pl/obrazy/file/zufawufilirolisag.pdfIn PDF document text
    • https://enville.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087bd82648dc---lozexovujemikedudasog.pdfIn PDF document text
    • https://goactive.hu/wp-content/plugins/super-forms/uploads/php/files/e5c01bfb958751b35ab862622271dada/54922736999.pdfIn PDF document text
    • http://househouse.it/userfiles/files/98635448096.pdfIn PDF document text
    • http://aggengr.com/uploads/CMS/file/75725212148.pdfIn PDF document text
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bee3b7af935---60156086762.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=types+of+future+contractPDF 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_off0000d6df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6DF 17992 bytes
SHA-256: aeaad2e7ac6d14e8b12f34a860ef827c326ff76cf8b898250d3839cb9ab50c55
font_01_sfnt_off000105f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105F6 10512 bytes
SHA-256: 2fb17d9af8b82033a02377d1375f46d731fe4bd4cecb893d2051c92e53e1eff3
font_02_sfnt_off00011e21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E21 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1