Malicious PDF — malware analysis report

Static analysis result for SHA-256 86dab6ba5aa44c64…

MALICIOUS

PDF

73.7 KB Created: 2021-09-25 13:42:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: e91aa61d41d6d4048953ad44fee38139 SHA-1: a15e13295b65e5f60bfb12aa61872f0d8893a4b8 SHA-256: 86dab6ba5aa44c64e1db5056ee6cd22fcbd092b0672e55d21ba41b76fd983d8f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected by ClamAV as Pdf.Phishing.Trojan and an ML classifier flagged it with high confidence. It contains numerous external URLs, including one that appears to be a redirector for search terms, suggesting a phishing or spamming campaign. The PDF structure and embedded content are heavily obfuscated, but the presence of multiple disposable hosting links and a link farm heuristic indicate a malicious intent to direct users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://allytemp.ru/uplcv?utm_term=convert+protected+epub+to+pdf PDF link annotation
    • https://cytokin.ca/upload/editor/file/xazawinejozozikiruvepina.pdfIn PDF document text
    • https://saunadlaciebie.pl/userfiles/file/98571787936.pdfIn PDF document text
    • https://datenglagi.com/contents/files/luporaxapufagexedawalor.pdfIn PDF document text
    • https://get-insurance.in/ckfinder/userfiles/files/41203816686.pdfIn PDF document text
    • http://galantemontagnana.it/ckfinder/userfiles/files/paviropiremukinowadom.pdfIn PDF document text
    • https://ltssinternational.com/res/wysiwyg/file/44186515386.pdfIn PDF document text
    • http://thenikharvconsultancy.com/userfiles/file/wamofipuwifakenemir.pdfIn PDF document text
    • http://www.prodomasa.com/ckfinder/userfiles/files/69202955313.pdfIn PDF document text
    • http://www.rafaellucenaehijos.com/ckfinder/userfiles/files/31424425436.pdfIn PDF document text
    • https://bbox.ru/images/shared/file/18829975587.pdfIn PDF document text
    • http://suamayin.biz/userfiles/file/durelanatin.pdfIn PDF document text
    • http://nemochem.cn/upload/files/50686735862.pdfIn PDF document text
    • https://hotelmitrutarija.com/uploaded/files/zebavujomawaruf.pdfIn PDF document text
    • https://ratoempat.com/contents/files/wusoforifiso.pdfIn PDF document text
    • http://bacsiha.com/public/ckfinder/userfiles/files/bilikixi.pdfIn PDF document text
    • https://icon-studios.com/userfiles/file/40829526644.pdfIn PDF document text
    • http://ctnphrae.com/ckfinder/userfiles/files/kolege.pdfIn PDF document text
    • http://sherwoodchambergolf.com/ckfinder/userfiles/files/5419107877.pdfIn PDF document text
    • http://dryoucosmeceutical.com/userfiles/files/saneriwitulazi.pdfIn PDF document text
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/1612ec44e0dc6d---bulogeruru.pdfIn PDF document text
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/161456f8e9d1b2---nikotarikelokexulowaso.pdfIn PDF document text
    • http://forti.in/userfiles/file/74586810650.pdfIn PDF document text
    • https://vidaleve.net/ckfinder/userfiles/files/59956172764.pdfIn PDF document text
    • http://gdlejia.com/uploadfile/files/20210916_205615.pdfIn PDF document text
    • http://ks-system.co.uk/ckfinder/userfiles/files/fuxobumolamudaninemukono.pdfIn PDF document text
    • 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_off0000b8a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8A0 18848 bytes
SHA-256: 7b29a0e07d52b8d2da9522a6c4d39bccb58f955795347dec94e7df26f8107f34
font_01_sfnt_off0000e8e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8E9 10480 bytes
SHA-256: 8374db15d27882f94ff6d5d1b9ea47dd1b46352716c00519204629471f941f12
font_02_sfnt_off000100a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100A7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1