Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec97660881c4da4f…

MALICIOUS

PDF

82.5 KB Created: 2021-09-15 20:13:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: fc5bbf02774be1e71b08e1947df53fa8 SHA-1: 9bb1f0b4e36222c8e8ef535e00a6ce412ced9e32 SHA-256: ec97660881c4da4f4fa70a9c193ea7da7b8f8ccdd32f69b881103cfd15d48365
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. Several heuristics identified the document as a link farm pointing to compromised CMS upload storage and disposable hosting, suggesting an attempt to distribute malicious content or phish users. The embedded URLs, such as http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141d43e2fe79---sanizij.pdf, are likely part of this distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1613b54d93fafd---87262612497.pdf In PDF document text
    • http://phukientubepxinh.info/gomsu/sanpham/anh/files/gojedojewetemubumetoxofa.pdfIn PDF document text
    • http://misterholidaysanprisco.it/userfiles/files/petiverejapubunepijebog.pdfIn PDF document text
    • https://emartdeko.pl/galeria/file/409676039.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fb3f17f6d4---luboletugerigujodonoba.pdfIn PDF document text
    • http://ambcavallon.eu/userfiles/files/vosuwezob.pdfIn PDF document text
    • http://geonatlife.es/ckfinder/userfiles/files/55328795406.pdfIn PDF document text
    • http://portalpr-b2b.es/img/user//file/_0222999001631522766.pdfIn PDF document text
    • https://avenue102.com/uploads/file/35188650845.pdfIn PDF document text
    • https://techlan.pl/files/file/64402171548.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/obr19sqanjecmqfajt472vq9n1/22900675416.pdfIn PDF document text
    • http://photo-ostrov.com/ckfinder/userfiles/files/govajilorezoniwili.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141d43e2fe79---sanizij.pdfIn PDF document text
    • http://sklenicky-obchod.cz/web/admin/fckeditor/userfiles/file/91288227790.pdfIn PDF document text
    • http://9y.bfage.com/upload/files/20210908113401.pdfIn PDF document text
    • http://nattukoottam.com/userfiles/file/vimapobuvalolukijelosabol.pdfIn PDF document text
    • https://argentinaproduct.com/ckfinder/userfiles/files/16982128844.pdfIn PDF document text
    • http://ingpiazza.eu/userfiles/files/dujojeb.pdfIn PDF document text
    • http://connectcontrol.net/files/userfiles/files/donalivavikato.pdfIn PDF document text
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/161310ec02e162---govemakosivatu.pdfIn PDF document text
    • https://brawlcall.jordanadams.com/ckfinder/userfiles/files/ginegakokezamif.pdfIn PDF document text
    • http://infinity-pro.ru/userfiles/file/53497692745.pdfIn PDF document text
    • http://kd-council.com/upfile/files/85034115258.pdfIn PDF document text
    • https://www.lorenzofranzone.it/wp-content/plugins/super-forms/uploads/php/files/ea7daf7e32cae0e56652d11e1ea1bb14/99209469820.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=set+orientation+android+tvPDF 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_off0000df59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF59 17968 bytes
SHA-256: df3e9b0fbedf0b47524e27421c91f3e0b7478a260ee243c4a80db86710a35b7a
font_01_sfnt_off00010d77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D77 10168 bytes
SHA-256: c1b9fe2c0ea63317df2a801aed998e881548fda2c9649e40d0021834b61b42e0
font_02_sfnt_off00012460.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12460 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1