Malicious PDF — malware analysis report

Static analysis result for SHA-256 21502b1ef67ab52e…

MALICIOUS

PDF

87.6 KB Created: 2021-09-10 14:26:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 6017dd5317a62493e5aa320951fa9384 SHA-1: 134e77f958881f0e38357184b003acf2805becff SHA-256: 21502b1ef67ab52e84f7432c1bfffbc1088b51275a16a270b341e97d732cd6cf
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or are part of a link farm designed to redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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://biosite.ru/images/news/file/wewilona.pdf In PDF document text
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/16137b35ac6bc9---77420884106.pdfIn PDF document text
    • http://skiflogistics.ru/userfiles/file/kuvovulaviwajixef.pdfIn PDF document text
    • http://foto-preiss.at/upload_files/files/84221122245.pdfIn PDF document text
    • https://alnahamgroup.com/userfiles/file/widom.pdfIn PDF document text
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1613798d410860---weginevovivazelos.pdfIn PDF document text
    • https://kirmatas.com/userfiles/file/80517239428.pdfIn PDF document text
    • https://ewastexperts.com/userfiles/files/59173583622.pdfIn PDF document text
    • https://royal-art.pl/uploads/userfiles/files/35311032223.pdfIn PDF document text
    • http://gr-chem.com/upload/files/43642362117.pdfIn PDF document text
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130cc7c9f9dd---jixivuxoravilokow.pdfIn PDF document text
    • http://narcisse.sk/editor_uploads/files/88251446560.pdfIn PDF document text
    • http://087334211.kad.tw/kads/ckfinder/userfiles/files/6392709639.pdfIn PDF document text
    • http://yacpa.org/yacpafiles/file/88683696940.pdfIn PDF document text
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161360a65af394---18120154823.pdfIn PDF document text
    • https://www.blackandwhite-salon.com/wp-content/plugins/super-forms/uploads/php/files/tmp/sises.pdfIn PDF document text
    • https://xn----7sbeo1acdy3adh.xn--p1ai/userfiles/file/jigazuxiluvogomebiv.pdfIn PDF document text
    • https://happycustomerservice.com/wp-content/plugins/super-forms/uploads/php/files/dfcb19074e85ed27574c42894f5f6ae2/62353201230.pdfIn PDF document text
    • http://honmamon-s.com/img_seminar/userfiles/file/senilaxopexovo.pdfIn PDF document text
    • http://alt-1c.ru/userfiles/file/13229769170.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=ready+player+one+full+movie+watch+onlinePDF 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_off0000ef79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF79 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010790.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10790 11128 bytes
SHA-256: f5f57ee21216d343ce4329197824b8f9a40a696d81e97d37fbd1065c7abd839c
font_02_sfnt_off00012156.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12156 18160 bytes
SHA-256: 34aee6f81f98f854eae2e98807d1194bf1e09d6fc81151f19b7caab340ebaa8d