Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5a0cc7b874489f8…

MALICIOUS

PDF

77.4 KB Created: 2021-09-18 12:07:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 9a904b10c3e3fcc69fbba65e1af62e74 SHA-1: 12a9dad457aed95b6437a54718a6fe9f1603eae7 SHA-256: b5a0cc7b874489f8bd09c22d79416992c4ad596345c8baee35637c6888f6551b
164 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, with heuristics indicating it is part of a link farm hosted on compromised or disposable domains. The presence of a 'download' button lure further supports a malicious intent to trick the user into downloading a payload. The URLs extracted point to various PDF files, suggesting a distribution mechanism for malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://geodeslaboratori.eu/userfiles/files/99630608171.pdf In PDF document text
    • http://gerastar.com/userfiles/file/susapezat.pdfIn PDF document text
    • http://holdemigny.fr/ckfinder/userfiles/files/borosaj.pdfIn PDF document text
    • http://vaonhaphatphap.com/images/uploads/files/sukuguruj.pdfIn PDF document text
    • http://electrogalicia.com/electrogalicia/recursos/archivos/58391480021.pdfIn PDF document text
    • http://engroupe.ca/aym_image/files/maxigotidipizaj.pdfIn PDF document text
    • http://www.dreamstoreonline.es/ckfinder/userfiles/files/88953485374.pdfIn PDF document text
    • http://benthanhsgfarm.net/images/uploads/files/26651367350.pdfIn PDF document text
    • https://chaletsuenodesol.de/files/doloterovukasuro.pdfIn PDF document text
    • https://osiindia.org/ckfinder/userfiles/files/95873982794.pdfIn PDF document text
    • http://fazendasaojudastadeu.net/fotosempresa/files/87452500649.pdfIn PDF document text
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613ff9f962e50---bowinexes.pdfIn PDF document text
    • https://kapokcmassage.com/uploads/files/202109052114041405.pdfIn PDF document text
    • https://cabsfromheathrow.com/userfiles/file/98833089846.pdfIn PDF document text
    • http://93564497.com/userfiles/58298769828.pdfIn PDF document text
    • https://www.xcelsus.de/wp-content/plugins/formcraft/file-upload/server/content/files/16138d7632752d---8689918888.pdfIn PDF document text
    • https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/q4thq73qbie22pibustgneu017/mulegupedep.pdfIn PDF document text
    • http://reicar.dk/userfiles/file/lenasatapinitopo.pdfIn PDF document text
    • http://tysons-cafe.com/uploads/files/37582072907.pdfIn PDF document text
    • http://lesbambousbleus.fr/ckeditor/upload/files/ropedejibogibijanawuwuvak.pdfIn PDF document text
    • https://churchosonline.com/wp-content/plugins/super-forms/uploads/php/files/29f8f4eb5ee8fe6d80f900b8f98b1f7c/xexelavefisuniw.pdfIn PDF document text
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/rivug2a0ca8c9mnl32q4q25va2/tegutixoler.pdfIn PDF document text
    • http://adance0112.com/upfile/editor/file/11615311027.pdfIn PDF document text
    • https://kungfuclasshongkong.com/louis/taichi/ckfinder/userfiles/files/mirasunimulisizasu.pdfIn PDF document text
    • http://apartament-krokus.pl/userfiles/file/65345784820.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=download+game+fast+and+furious+tokyo+drift+for+androidPDF 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_off0000c706.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC706 11092 bytes
SHA-256: fa8fb67f3ca88c111418081982634a5a377d7ca1f57fd0a131bcac71bacee300
font_01_sfnt_off0000e0ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0BA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f8cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8CC 17340 bytes
SHA-256: ae7351dda79aa7d0ba01491ac6ac5bc4c8a9ebc1932d0c03ff52408ac9920abe