Malicious PDF — malware analysis report

Static analysis result for SHA-256 2044f753e1defc1a…

MALICIOUS

PDF

83.1 KB Created: 2021-09-08 00:06:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 3361e06035f3e94d02101b9bef8545f7 SHA-1: 29e3534a2f8ebd8059e1c73c5447a7f7cf5a2212 SHA-256: 2044f753e1defc1ac0e34a446f67debb86d563ad31d9276a7df55c0a806ed02d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected as a malicious PDF by ClamAV and an ML classifier, indicating it is likely a phishing or trojan delivery mechanism. Heuristics identified it as a link farm pointing to compromised WordPress uploads and disposable hosting, suggesting an attempt to obscure the final payload. The presence of invoice-related language further supports a lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 7

  • 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://massarentearchitettura.com/userfiles/files/maxofafaxerabikof.pdf In PDF document text
    • https://gtnet-engine.com/ckfinder/userfiles/files/98649915368.pdfIn PDF document text
    • http://chaukitchen.com/uploads/files/vebedoxesalenamote.pdfIn PDF document text
    • https://dgssu.com/upfolder/e/files/20210701012729.pdfIn PDF document text
    • http://ekstelekom.com/userfiles/file/wusifewilexorupipaf.pdfIn PDF document text
    • https://photojet.bg/userfiles/file/lexojububonupijopuvami.pdfIn PDF document text
    • http://angarakshaksecurity.com/userfiles/file/19354885944.pdfIn PDF document text
    • https://turasmobilya.com/img/editor/image/file/sadodoponopagevizalixezel.pdfIn PDF document text
    • http://gongotour.com/FileData/ckfinder/files/20210826_4D3075FAA5C27556.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b3ab36a8ec.pdfIn PDF document text
    • https://parfumzone.ro/files/file/kodef.pdfIn PDF document text
    • https://motionslam.com/wp-content/plugins/super-forms/uploads/php/files/3e565282a0cdb73a1ec2fa8d478c65bf/98990640485.pdfIn PDF document text
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607c21a381685---2854886235.pdfIn PDF document text
    • https://www.spitalmoldovanoua.ro/ckfinder/userfiles/files/zuxufamanet.pdfIn PDF document text
    • http://africanhairbraidingsalon.com/userfiles/file/melobusodebajok.pdfIn PDF document text
    • http://jatyn.cn/upfiles/202105/file/1621154967.pdfIn PDF document text
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/808919d81d184ff820f51d5934ccc0c1/wepitobaxipuma.pdfIn PDF document text
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/1ee5b5c0f4e5b45b4420532eca1148d0/9909678637.pdfIn PDF document text
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/46b5ab583796fb7fed8974850ca043ac/sigugibefivetagakog.pdfIn PDF document text
    • https://eingangrad.ch/userfiles/files/wifuxawuditefu.pdfIn PDF document text
    • https://www.andyselfstorage.co.uk/wp-content/plugins/super-forms/uploads/php/files/imn6apegnmb198u3r1ofev3pqg/74313872825.pdfIn PDF document text
    • https://him-home.ru/wp-content/plugins/super-forms/uploads/php/files/72fe6982a85fa28f557125c97f642d66/42109607383.pdfIn PDF document text
    • https://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/e64fca9be46339a45c2c719967a38365/wasaxaluvekesegogiro.pdfIn PDF document text
    • https://mut-zur-veraenderung-hambuch.de/userfiles/file/kufowiburasonaze.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=barclays+online+banking+pdf+statementPDF 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_off0000dd78.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD78 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f58f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF58F 11360 bytes
SHA-256: c3ea35be86df7e5f293a822836802081042ae9f83717c0baf3ab3d8074992b71
font_02_sfnt_off00010ff5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FF5 17920 bytes
SHA-256: 31ac0bff4fd1e04f8074f11e02121a98212c707f569cf2afe229db26229085a3