Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8b7823f88662df9…

MALICIOUS

PDF

79.7 KB Created: 2021-09-19 08:51:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: eb7ceafc783d5d2e2ae9f04d7b263d94 SHA-1: 7232f05b17f9bb613ad8a8f69d1ea56bd309c434 SHA-256: a8b7823f88662df904ffb43bc688aab85db75e2fac92d842e02618978685b4ee
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous external URIs, many of which are link farms pointing to other PDF files, suggesting a phishing or malware distribution scheme. The presence of a link with a 'utm_term' parameter related to a game download further supports the lure-based attack pattern. While no scripts were explicitly extracted, the PDF structure and URL patterns are indicative of malicious intent, likely to redirect users to malicious sites or download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 https://archism.ru/uplcv?utm_term=minecraft+free+1.17+pe PDF link annotation
    • http://twsl.mingann.info/upload/ckfinder_temp/files/20210903134348.pdfIn PDF document text
    • https://oilbasaro.com/web/images/ckfinder/files/20210919024901.pdfIn PDF document text
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/16138e572edba5---70596543339.pdfIn PDF document text
    • https://pelletier-tp.fr/ckfinder/userfiles/files/lusumabavivejitagalatud.pdfIn PDF document text
    • http://aloisiquadri.it/userfiles/files/79784108905.pdfIn PDF document text
    • http://baschin-heizung.com/meineBilderAlbertGrundschule/file/lubigi.pdfIn PDF document text
    • http://perles-del-beya.com/userfiles/file/rujonexadazegonuwubowibu.pdfIn PDF document text
    • http://saint-party.com/media/file/39632905689.pdfIn PDF document text
    • http://nedvizhimost-v-sharm-el-sheikhe.ru/uploads/files/59513046022.pdfIn PDF document text
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/161313bcd67172---xatijunimafumo.pdfIn PDF document text
    • http://anhbanglaw.com/userfiles/file/ninogutewil.pdfIn PDF document text
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/16130993e3c468---latodapos.pdfIn PDF document text
    • http://dr-temt.ru/images/file/28124696928.pdfIn PDF document text
    • https://ph789.com/pinhsuan/files/file/4602555796.pdfIn PDF document text
    • http://magogaralbamoble.com/galeria/files/63938363640.pdfIn PDF document text
    • http://tsyrulnikov.ru/upload/file/97661181630.pdfIn PDF document text
    • https://clickbox.ro/images/file/koposawomozurob.pdfIn PDF document text
    • https://rajaketiga.com/contents/files/siteraporimokowalidu.pdfIn PDF document text
    • http://hoya-system.com/uploads/files/202109170718277340.pdfIn PDF document text
    • http://twtipa.com/upfile/files/2021/09/16/39134442369.pdfIn PDF document text
    • http://teraval.cz/res/file/36277208985.pdfIn PDF document text
    • http://heaig.org/editor/ckfinder/userfiles/files/zomodosajekaralukazejupar.pdfIn PDF document text
    • https://khonggiansachhanoi.vn/uploads/files/89375387389.pdfIn PDF document text
    • http://cesarrodarte.com/userfiles/file/basumusolotoz.pdfIn PDF document text
    • http://kooijobs.in/ckfinder/userfiles/files/86838788087.pdfIn PDF document text
    • http://inwama4.vn/webroot/img/files/71545746697.pdfIn PDF document text
    • 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_off0000d5b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5B7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000edce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDCE 10300 bytes
SHA-256: 9b87546c922db1102c6c06e66b7322fc0ae64a935a33ed063f9622446541779e
font_02_sfnt_off00010532.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10532 16976 bytes
SHA-256: d752bc835064a3653ce85ce78620a3e00f7f2681853eefc345c075ebd5448cf3