Malicious PDF — malware analysis report

Static analysis result for SHA-256 e810b7d2b11a425d…

MALICIOUS

PDF

80.4 KB Created: 2021-09-20 11:11:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: bf23401f5b6f28c6ee68bac6311faa74 SHA-1: ea5380e1ab1afaa1d94fff4e19f5923846a2a502 SHA-256: e810b7d2b11a425d160dfe3578e6d2f820126b4c17f0909326266b245cf0142c
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to disposable hosting or compromised CMS upload storage, indicative of a link farm used for phishing or malware distribution. The ClamAV detection and ML classifier strongly suggest malicious intent. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond its structure as a link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 6

  • 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.
  • 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://pixomot.ru/uplcv?utm_term=free+market+apk PDF link annotation
    • http://andrelandberg.com/userfiles/file/41914471175.pdfIn PDF document text
    • http://rakkhunnursinghome.com/user_img/files/xixoluk.pdfIn PDF document text
    • https://supportsystemsvainc.com/home/ssvi/public_html/ckfinder/userfiles/files/komukorulinedupugutilisa.pdfIn PDF document text
    • http://cnzhongkui.com/fckeditor/editor/filemanager/connectors/php/uploads/file/020526547945.pdfIn PDF document text
    • https://thegmsbihta.in/userfiles/file/sawojugowixuriwi.pdfIn PDF document text
    • http://synergyproperty.com/images/files/midixifibuw.pdfIn PDF document text
    • https://phu-komplex.pl/pliki/file/fojosivulifulugazisopimuw.pdfIn PDF document text
    • http://avsa.org/sites/default/files/images/files/92579559520.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/16147bf299617b---degetanovazufenezekexat.pdfIn PDF document text
    • http://laboratoriologos.it/userfiles/files/2814090377.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614082119f929---febonasajobomozunamufisa.pdfIn PDF document text
    • http://goref.ru/files/file/35336231387.pdfIn PDF document text
    • http://agapetown.net/ckfinder/userfiles/files/51107635273.pdfIn PDF document text
    • https://sieuthimayphat.com/ckfinder/userfiles/files/43880251409.pdfIn PDF document text
    • http://pro-customer.de/userfiles/file/jeludufa.pdfIn PDF document text
    • https://coastalstudio.com/images/main/file/xezarekuf.pdfIn PDF document text
    • https://longhoang.vn/upload/files/60509755934.pdfIn PDF document text
    • http://luluscafeonline.com/uploads/files/selupeg.pdfIn PDF document text
    • https://nieruchomosciturystyczne.eu/files/file/57737801484.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/161394f01e4486---58607941560.pdfIn PDF document text
    • http://berbun.com/user_img/file/sosarerawivuzenomub.pdfIn PDF document text
    • http://gps-tw.com/CKEdit/upload/files/41714246327.pdfIn PDF document text
    • https://yaofangpeixun.com/upload/files/rikarupakezogulomojukev.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_off0000d16a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD16A 20236 bytes
SHA-256: a3ae2757ae4f9dbc7d45a805a1cdc377289eb8aec27f81d96c5c140b9979e34c
font_01_sfnt_off000106a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106A1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011eb7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EB7 9952 bytes
SHA-256: c31d9208ee32bdc0d6719e487d1c6dfd0e24aec44efaaf448db32e5c9b3a6244