Malicious PDF — malware analysis report

Static analysis result for SHA-256 6669e69c9cc9f8ba…

MALICIOUS

PDF

75.9 KB Created: 2021-09-11 00:56:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 58e19129f83514f930fbe4abd5fa966c SHA-1: ef9e04ae4d62d95d42d4424910d158129bbc4f03 SHA-256: 6669e69c9cc9f8ba276e4aaf9b0c1dd6ba96df6276361a942432689dffcd60df
156 Risk Score

Malware Insights

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

The PDF document was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, suggesting a link farm designed to redirect users to malicious sites. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, lacking clear user-facing content but containing numerous embedded URIs.

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://1day2night.com/UserFiles/file/51191792375.pdf In PDF document text
    • https://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/9nko8820259adfh44htohvph36/78876138428.pdfIn PDF document text
    • http://mobiliteit.nu/files/wawaxav.pdfIn PDF document text
    • https://parisautotravel.com/wp-content/plugins/super-forms/uploads/php/files/s83p9mtd32vaugk7tps6k5jue1/jemesonifavudimusotajisop.pdfIn PDF document text
    • http://uptownherndon.com/uploads/files/66701572869.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/16136d6022e354---78469721977.pdfIn PDF document text
    • http://mitsubishilongbien.vn/images/ckeditor/files/xigakuwe.pdfIn PDF document text
    • https://baxsporthorses.nl/userfiles/file/18133271562.pdfIn PDF document text
    • http://busankid.com/webfiles/board/file///zapimodavejezaf.pdfIn PDF document text
    • https://austarpharma.austarchina.com/upload/files/kaxuwolularojumerafi.pdfIn PDF document text
    • http://leguido.net/files/13007051639.pdfIn PDF document text
    • http://kaies.net/upfiles/2109110352065668142o05pz.pdfIn PDF document text
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16131706cc80ba---tulirubidufaratafap.pdfIn PDF document text
    • https://cottonweb.net/userfiles/file/71623703598.pdfIn PDF document text
    • http://24cvety.ru/upload/files/geruxoxoduzut.pdfIn PDF document text
    • http://oikoscoccatoarchitettura.com/userfiles/files/fimosukifoxewasum.pdfIn PDF document text
    • https://myclubowners.com/userfiles/files/fulijolerumafez.pdfIn PDF document text
    • http://citadelcaralarms.com/userfiles/file/33662693215.pdfIn PDF document text
    • https://aromamarketing.md/img/files/dofakagofaxosemi.pdfIn PDF document text
    • http://op-gold.com/ck_image/files/zofajiv.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/640d14ace51897b171cdc6d89e4921df/fonafug.pdfIn PDF document text
    • http://belovosushi.ru/files/negogoto.pdfIn PDF document text
    • http://cleanking.net/userData/board/file/93676384830.pdfIn PDF document text
    • https://ayurmitra.com/files/file/24282233914.pdfIn PDF document text
    • https://ajwatravel.com/wheelmarine/userfiles/file/94801814895.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=guitar+tuner+versi+lamaPDF 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_off0000c6b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6B6 17060 bytes
SHA-256: 98e31c710ee5d2599dcc3cf4e375e0ea9f035f46417ee7a20972e7ba8bd86e43
font_01_sfnt_off0000f2c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010ae0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AE0 10356 bytes
SHA-256: cd5c5b569582abb901f5767fc627093755403e65e785c0671245d5279c196ca0