Malicious PDF — malware analysis report

Static analysis result for SHA-256 b16c7c5dc42f9216…

MALICIOUS

PDF

70.7 KB Created: 2021-09-06 04:48:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 6e91ab0d5e6ce3ffca857b9af7f8eb61 SHA-1: 3704c53baeb57118440e81d6e2cb92e9e168d001 SHA-256: b16c7c5dc42f9216a1549a2ab11b5424b1bf0a8066ec65d34ec9215c5948f9bf
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely facilitates the redirection or download of further malicious content, contributing to a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 https://www.sadcmedia.com/wp-content/plugins/super-forms/uploads/php/files/a3nohmm3dm9j6hk4vlkat9ql1h/14077461749.pdf In PDF document text
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609fa244edd2c---pusibajodipel.pdfIn PDF document text
    • https://chungcungoaigiao.net/uploads/files/visirige.pdfIn PDF document text
    • http://nw-line.ru/generic/uploaded/durexunuwajajejotojoxedo.pdfIn PDF document text
    • https://www.afoa.org.ar/backend/ckfinder/userfiles/files/losuxalalufowikezup.pdfIn PDF document text
    • https://martensmgt.com/business_school/uploads/file/6080825203.pdfIn PDF document text
    • https://vieclamxaydung24h.com/upload/files/92757734827.pdfIn PDF document text
    • http://showpalmedical.com/userfiles/88399138072.pdfIn PDF document text
    • https://thepainter.asia/upload/files/gerilunapigufowi.pdfIn PDF document text
    • https://zhbiotech.com/CKEdit/upload/files/xinikenobolidelukabimat.pdfIn PDF document text
    • http://www.cenlaenvironmental.com/siteuploads/editorimg/file/80636227453.pdfIn PDF document text
    • https://prolocolidodisavio.org/ckfinder/userfiles/files/59958359303.pdfIn PDF document text
    • http://bpabv.nl/uploadfiles/file/tizoduxojupa.pdfIn PDF document text
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/160951b149b8e0---tokaganedom.pdfIn PDF document text
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/0o53gq79u2hhscvl7f2quv2anv/93734477909.pdfIn PDF document text
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160aac2a8004b5---99549953284.pdfIn PDF document text
    • http://szjglaw.com/uploadfile/file/2021081212055773499.pdfIn PDF document text
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/57038e6f1cc9e6bd70b685f4a97d9fe5/7680740137.pdfIn PDF document text
    • https://basisangka.com/contents/files/zilafolabojidotewasovur.pdfIn PDF document text
    • https://corumosmanlimakina.com/js/ckfinder/userfiles/files/wafakuk.pdfIn PDF document text
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075773ecd52a---92459991081.pdfIn PDF document text
    • https://ukdirectremovals.com/wp-content/plugins/super-forms/uploads/php/files/245351e0111466c8b05289c484476d39/sixenopego.pdfIn PDF document text
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/a78d1ecfdb196d9bf5acb5feed3e8dbd/sejixowijobilubapos.pdfIn PDF document text
    • https://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/ac33e84453b53a5601172adf484dd508/29031625543.pdfIn PDF document text
    • https://aplusadvance.com/naver_editor/data/file/21345855747.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=percent+word+problems+worksheet+8th+grade+pdfPDF 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_off0000b6d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB6D6 11504 bytes
SHA-256: 951b61b4bbaff6d41aa05e175789451467b69732c369d8fab6c1e0c6acbe4b26
font_01_sfnt_off0000d187.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD187 14316 bytes
SHA-256: 95f7a3e13e3a21e7f50cd46dd646a0e852270bf05f19730c4b003259d84dded3
font_02_sfnt_off0000f4d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4D3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1