Malicious PDF — malware analysis report

Static analysis result for SHA-256 befc37b37f5539a4…

MALICIOUS

PDF

86.0 KB Created: 2021-07-02 07:18:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: ac41f4de8abf7a92727681c2b1939e7b SHA-1: e3e0b7a6180193b3707980dc1a24a0e8fa249119 SHA-256: befc37b37f5539a44ab5851227b94ec55c8afcdd74455cf458259d5e22d2fb04
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to unknown PDFs hosted on compromised WordPress sites. This structure strongly suggests a link farm designed to lead users to malicious content. The ClamAV detection and ML classifier further support its malicious nature, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://blog.crowdly.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fcfb1d7eb0---vilakifebimis.pdf In PDF document text
    • http://scandirent-new.ru/uploads/assets/file/97512306394.pdfIn PDF document text
    • http://jameshamiltondds.com/clients/6/6c/6cc67b5d90347a591bf4e9c0b97a5143/File/51920961154.pdfIn PDF document text
    • https://chefinhogourmet.com/wp-content/plugins/super-forms/uploads/php/files/1b7b21c760d9e942d734832e50680e82/91237402323.pdfIn PDF document text
    • http://myexamadvisor.com/fck_uploads/files/mixekekofisabatedo.pdfIn PDF document text
    • http://kfbi.ru/content/file/kixafa.pdfIn PDF document text
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/48640db5d07f441e9432839adc6b294e/3112646586.pdfIn PDF document text
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/82c20b1fd219df2ef34b4bd4a9714ace/wiximokofuranirudi.pdfIn PDF document text
    • http://m2m2design.com/userfiles/50975470821.pdfIn PDF document text
    • https://festivalecolo.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16083459953135---wusononolovedava.pdfIn PDF document text
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/u0eko6ntbdpjo6cj6i73luhqbn/fugapegi.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16083749f840b2---34145760469.pdfIn PDF document text
    • http://wadirumshootingstars.com/userfiles/file///40017042236.pdfIn PDF document text
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/160741f122ce3d---84263281718.pdfIn PDF document text
    • http://teplospectr.ru/images/files/49151354112.pdfIn PDF document text
    • https://ifacemount.com/wp-content/plugins/super-forms/uploads/php/files/6uu11k0o55l26rqp91oco5o2l9/vexitazusalutox.pdfIn PDF document text
    • https://canadiancontractorservices.com/wp-content/plugins/super-forms/uploads/php/files/o2sulsoqkkhqdr3r5590upm906/34489858859.pdfIn PDF document text
    • https://iescolumbus.org/wp-content/plugins/super-forms/uploads/php/files/4956ea7aea86956783296f8d18489d23/12366533465.pdfIn PDF document text
    • https://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/b624d1db15a1a976b1181e880d7649eb/wagaxa.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160da5a2f641e7---rezanikewuxibex.pdfIn PDF document text
    • http://laduses.nl/image/file/36449189333.pdfIn PDF document text
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092c0db9048a---luniro.pdfIn PDF document text
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093aae0aec3c---64045302519.pdfIn PDF document text
    • https://beautifullifeuk.com/wp-content/plugins/super-forms/uploads/php/files/d918f6f2bdeac54c9ba48cf8680786fe/93774107517.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=drying+walnuts+in+shellPDF 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_off0000ef27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF27 10568 bytes
SHA-256: e10da15d30f0b889bdf9b19cf596257bc1177c40f2f1ab369d43fa08120838e6
font_01_sfnt_off0001074f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1074F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011f61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F61 16700 bytes
SHA-256: 87c0bcad4555f86e8362a9be89578596958bf5ff9ee68906ef98e4e81ac988b5