Malicious PDF — malware analysis report

Static analysis result for SHA-256 71f212fdd8672de3…

MALICIOUS

PDF

71.1 KB Created: 2021-09-10 12:28:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 079efacd6adf74661b8b033a40a04458 SHA-1: df1df5844c8aa8090694b162e3d7c6d268bedbd1 SHA-256: 71f212fdd8672de3cca3f6bb69ae6fea84975a0b4846fd5c76d95bccc85348f1
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs that form a link farm, with several pointing to compromised CMS upload storage and disposable hosting. The ML classifier strongly indicated maliciousness. The presence of multiple external URIs and link farms suggests an attempt to redirect users to potentially malicious sites or for SEO manipulation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • 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://synerhu.ru/uplcv?utm_term=akuapem+twi+bible+apk+download PDF link annotation
    • http://zulassungsservice4you.de/bilder/file/bozaguvemuwupeginewexibem.pdfIn PDF document text
    • https://cengilli.com/icerik_images/file/41758157951.pdfIn PDF document text
    • http://flexa.cz/docs/file/83517454126.pdfIn PDF document text
    • http://togclick.com/media/userFckfiles/file/siviziw.pdfIn PDF document text
    • http://www.enjoyvaltellina.it/admin/ckfinder/userfiles/files/68693646085.pdfIn PDF document text
    • http://hasdeu.md/data/userfiles/files/wefowirafanoseli.pdfIn PDF document text
    • http://benthanhsgfarm.net/images/uploads/files/61650155601.pdfIn PDF document text
    • http://planbmedia.hu/files/xezutenudidatimalogakawa.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134a2f0e26f8---gubuzidewe.pdfIn PDF document text
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/161324c35a633b---68280165827.pdfIn PDF document text
    • http://photo-preiss.com/upload_files/files/zopuxobumufaguvub.pdfIn PDF document text
    • https://www.temsilcisitesi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613107114fc20---72458224710.pdfIn PDF document text
    • https://guineaservicesproviders.com/gsp/files/20775254399.pdfIn PDF document text
    • https://hediyelikhanem.com/calisma2/files/uploads/wusuvesi.pdfIn PDF document text
    • https://sharzh-ufa.ru/wp-content/plugins/super-forms/uploads/php/files/cde52b86e7b7288c8d10d271bee6c1d0/jesunonovusasazuradelus.pdfIn PDF document text
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137f732ea7ce---serawelixufagowenunaxil.pdfIn PDF document text
    • http://streetnn.ru/data/upload/ck/files/kizubetalukivepuja.pdfIn PDF document text
    • https://heyratacademy.ir/file/fapogivoxikajutibosolalil.pdfIn PDF document text
    • http://interroadholland.nl/userfiles/file/juwakemawibixuvedit.pdfIn PDF document text
    • http://snbedu.com/uploadfile/file///2021090711024995.pdfIn PDF document text
    • http://s2group.pl/userfiles/file/nefukumozo.pdfIn PDF document text
    • https://medicabg.com/uploads/wysiwyg/files/podarulojeb.pdfIn PDF document text
    • http://administratieindex.nl/images/uploads/76987451127.pdfIn PDF document text
    • https://renebeumer.nl/userfiles/file/mibimulonenoxulatapovudi.pdfIn PDF document text
    • http://xn--h1acbpobggs.xn--p1ai/data/files/pibekofofu.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_off0000b861.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB861 10684 bytes
SHA-256: fba3e906b554f665c6ce7d3e0942bb7c5f4b62c9fdfc730fc975a956eb2b4a77
font_01_sfnt_off0000d0a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0A8 15020 bytes
SHA-256: c55b79424806a0bb049861ad04e58a98fd46883d9bfd72976a33db605a3b4535
font_02_sfnt_off0000f695.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF695 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1