Malicious PDF — malware analysis report

Static analysis result for SHA-256 f367a523b7f480a2…

MALICIOUS

PDF

81.3 KB Created: 2021-09-10 16:57:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 3c923fa9844ede0261b7f5c5e799d2e6 SHA-1: f574c2696945c6e7788cd33acf95f62a1b486ba4 SHA-256: f367a523b7f480a2583e5d160b975050ff5037779f7543f66ee7f9c83cdd0be1
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to manipulate search engine results or direct users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://birkhoffhi.com/userfiles/files/kexunelujizasodezulijumir.pdf In PDF document text
    • https://ahha.az/userfiles/file/lazosom.pdfIn PDF document text
    • http://www.ez4parcel.net/upfile/files/2021/09/09/39879273514.pdfIn PDF document text
    • http://rickgrisolia.com/userfiles/files/konutasalav.pdfIn PDF document text
    • http://asja.ua/userfiles/file/veweto.pdfIn PDF document text
    • http://bluecars.pl/userfiles/file/wezariwazapopajada.pdfIn PDF document text
    • http://kaus21.com/userData/board/file/surifezovejazu.pdfIn PDF document text
    • http://women-for-marriage.com/ckfinder/userfiles/files/63216288288.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/dbeg8s2go970jv3ikfut7gi3j0/75531147699.pdfIn PDF document text
    • https://pmsp-me.com/userfiles/files/zumamibogavabum.pdfIn PDF document text
    • https://danielstrehlau.com/userfiles/file/pelupadunujigugon.pdfIn PDF document text
    • http://zbirozskepodzamci.cz/userfiles/32035354785.pdfIn PDF document text
    • https://www.horisunmauritius.com/wp-content/plugins/super-forms/uploads/php/files/2c7af9d5e5ae9ce80a830a3ae98a2b45/63160313740.pdfIn PDF document text
    • https://yam-token.com/business_school/uploads/file/51806974205.pdfIn PDF document text
    • https://ateliersmq.com/pevron/www/img/file/wanagiravidexogamodefa.pdfIn PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/9d66429a5fc90e7125529a4e8e4309a3/86524823154.pdfIn PDF document text
    • http://onlinemidias.com/ckfinder/userfiles/files/bevujideselozo.pdfIn PDF document text
    • http://postelezmasivu-brno.com/ckfinder/userfiles/files/latoz.pdfIn PDF document text
    • http://cancunday.com/travela/img/files/gojepejapamute.pdfIn PDF document text
    • http://hamdannepal.com/userfiles/file/nobirifufe.pdfIn PDF document text
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133e4a8ca28d---62274437747.pdfIn PDF document text
    • http://falconfam.com/ckfinder/userfiles/files/93300634757.pdfIn PDF document text
    • http://www.anglometais.com.br/adm/Editor/ckfinder/userfiles/files/46303703086.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=android+su+nokia+lumia+800PDF 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_off0000d7bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7BF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000efd6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFD6 10684 bytes
SHA-256: 282f0aa774e848d10fc2a1aaec2e71b93a162190f8b76d0ab4a121af5f1f4e58
font_02_sfnt_off00010842.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10842 18276 bytes
SHA-256: 063cc9d7e1d320cc3d3f73b5309482c593dd6c6124379515954e10491b1afd0c