Malicious PDF — malware analysis report

Static analysis result for SHA-256 5123780ed50eadd6…

MALICIOUS

PDF

76.7 KB Created: 2021-09-24 20:49:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 192cbc3bcdb8ddd44a6124ea6c360818 SHA-1: dd91a6a7e2d0758eb1fa91d792a87afad8b8447c SHA-256: 5123780ed50eadd626921a18d359f844b2d5993b236a5a01341721d8933295c1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple domains, some of which are identified as compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://ouhkpthaa.org/userfiles/47450900940.pdf In PDF document text
    • http://luckdidea.com/ckfinder/images_store/files/34935560249.pdfIn PDF document text
    • http://humanitool.ru/userfiles/file/pamitasixefiw.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/3491663f68bc34a23f3654aac2d9a773/49544144316.pdfIn PDF document text
    • http://gr-chem.com/upload/files/76048395674.pdfIn PDF document text
    • https://airin.lv/images/userfiles/file/54144498286.pdfIn PDF document text
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/16140c5ce827d3---dutobolukej.pdfIn PDF document text
    • http://indemo.pl/Image/files/vavozarul.pdfIn PDF document text
    • http://stacjaregeneracja.pl/userfiles/file/62048998706.pdfIn PDF document text
    • http://flapboxes.custompackageboxes.com/userfiles/files/36094899947.pdfIn PDF document text
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fd248c5240---fatofadegumega.pdfIn PDF document text
    • http://miet-boot.ch/images/uploadedimages/file/vupewefejadilifum.pdfIn PDF document text
    • https://corpus.bg/files/fck/file/sebatizowaxurij.pdfIn PDF document text
    • http://bociany.sk/media/file/sifaminewokikotef.pdfIn PDF document text
    • https://lionkingbali.com/uploads/file/79838308800.pdfIn PDF document text
    • https://www.huaikrachaohospital.go.th/assets/global/lib/ckfinder/userfiles/files/futapobuvusesiveveg.pdfIn PDF document text
    • https://cursosadistanciayonline.com/medios/files/22787917804.pdfIn PDF document text
    • http://dorrstrechy.cz/UserFiles/File/52714271021.pdfIn PDF document text
    • http://rvhifi.cz/files/file/74037011585.pdfIn PDF document text
    • https://ev-owners.jp/userfiles/files/29798419011.pdfIn PDF document text
    • http://marienoellebermond.com/img/uploaded/file/fefikisifivi.pdfIn PDF document text
    • http://kalmi.ru/upfiles/files/pavuviti.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=%D1%81%D0%BA%D0%B0%D1%87%D0%B0%D1%82%D1%8C+tubemate+%D0%B4%D0%BB%D1%8F+%D0%B0%D0%BD%D0%B4%D1%80%D0%BE%D0%B8%D0%B4+%D0%BD%D0%B0+%D1%80%D1%83%D1%81%D1%81%D0%BA%D0%BE%D0%BCPDF 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_off0000b595.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB595 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cda7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDA7 23300 bytes
SHA-256: 7e06e3f20899893584671e054cbfa9406c0f9daedd13a1fcb979a4ae8675ffa3
font_02_sfnt_off000107c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107C3 11532 bytes
SHA-256: 4901b6b88fef2222ed0e844b093ccf46cd087a3227214d19420910e14a158a51