Malicious PDF — malware analysis report

Static analysis result for SHA-256 2f122e3671d864b8…

MALICIOUS

PDF

72.4 KB Created: 2021-09-30 11:07:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 99708b7a454a79324ee546da8916628b SHA-1: fae4a85372f9abbd85d20d20ec3886126a6c4087 SHA-256: 2f122e3671d864b896356048105aac50c13447abd12fe59c4feb8a4253236f9d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document identified as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs pointing to various websites, many of which appear to be compromised WordPress installations or disposable hosting. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM indicates a link farm on disposable hosting, suggesting an attempt to distribute malicious content or phish users. The presence of external URIs and link farms strongly suggests the document's purpose is to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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 https://coretry.ru/uplcv?utm_term=file+hide+expert+pro+apk PDF link annotation
    • http://www.biharikft.hu/bihari-admin/ckfinder/userfiles/files/18741042375.pdfIn PDF document text
    • http://ayurvedicclinic.org/userfiles/file/11380594415.pdfIn PDF document text
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138fd0370282---nigekazajokagenifegas.pdfIn PDF document text
    • https://nikken-engineer.jp/export/sd205/www/jp/r/e/gmoserver/8/6/sd0748886/nikken-engineer.jp/fckeditor/upload/file/12526556649.pdfIn PDF document text
    • http://tatagz.com/uploadfile/files/fobazimonekug.pdfIn PDF document text
    • http://studiopetrilli.it/userfiles/files/nukixanu.pdfIn PDF document text
    • https://clic-essc.ch/ck/ckfinder/userfiles/files/batumo.pdfIn PDF document text
    • http://4seasonstours.in/userfiles/file/85833833728.pdfIn PDF document text
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16146ff5171174---90276930957.pdfIn PDF document text
    • https://isleo.com/i_photos/file/52918620375.pdfIn PDF document text
    • http://abbuffalowings.com/uploads/files/kipezanumopazuvaxapese.pdfIn PDF document text
    • http://www.omt.ntou.edu.tw/ckfinder/userfiles/files/71867478499.pdfIn PDF document text
    • https://www.disbel.es/ckfinder/userfiles/files/minemufutilimoputuwun.pdfIn PDF document text
    • http://pzhjintai.com/upload/files/81436886685.pdfIn PDF document text
    • https://syntellect.ru/Repository/file/lisatumodekikema.pdfIn PDF document text
    • http://adasbruiloften.nl/userfiles/file/suvowuwe.pdfIn PDF document text
    • http://lawcab.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613f66386d462---65118264936.pdfIn PDF document text
    • http://www.stadion-zarya.ru/ckfinder/userfiles/files/vabuzufadug.pdfIn PDF document text
    • https://www.iieng.org/editor/ckfinder/userfiles/files/55124173233.pdfIn PDF document text
    • https://abrasco.org.br/ckfinder/userfiles/files/sakim.pdfIn PDF document text
    • https://sdhouse.info/ckfinder/userfiles/files/38535583565.pdfIn PDF document text
    • https://khambenhxahoi115.com/images/files/41029155049.pdfIn PDF document text
    • http://7m-shop.com/userfiles/file/54634010132.pdfIn PDF document text
    • https://sua.vn/uploads/userfiles/file/wenaduranines.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_off0000b555.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB555 18232 bytes
SHA-256: 9f3b747a21fbedab1b30158511f63fe9e73e6eb65645b7c7151ee91ceede72a3
font_01_sfnt_off0000e44c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE44C 10388 bytes
SHA-256: 4cc6aa8a202676b3c7ae93debbcb763e713df4808401d8f394cf739e02b5bcfa
font_02_sfnt_off0000fbdd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBDD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1