Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7baf0df184e6adc…

MALICIOUS

PDF

71.7 KB Created: 2021-09-20 05:59:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: ee303bc5ffff077788a631e9aa9604eb SHA-1: 6acca8fd5456e04a6a359ffca07a2ee3b0e2ceef SHA-256: b7baf0df184e6adcb25ada5ccecea476591c2c9a124f39d97b9525aa9778de5b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. It contains numerous embedded URLs, many pointing to compromised WordPress sites, suggesting a link farm used for SEO manipulation or to host malicious content. The presence of external URIs and link farms indicates an attempt to redirect users to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://crysiq.ru/uplcv?utm_term=android+stock+audio+recorder PDF link annotation
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/754a883d3ae4b72398776e931edbef97/nafovizabotinowi.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613b2e4621949---jumobuzote.pdfIn PDF document text
    • http://texmet.pl/userimages/file/vafagatomuwexa.pdfIn PDF document text
    • http://madinaboys.com/easydo%20v2.00/files/uploads/61931920187.pdfIn PDF document text
    • https://1tlstar.com/storage/uploads/files/sodeburubelug.pdfIn PDF document text
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/910b674047a3d5c69087fec02754acb3/gipinezenawekuse.pdfIn PDF document text
    • http://thienminhgroup.com/uploads/userfiles/file/lililu.pdfIn PDF document text
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613c9bbd15cee---fepidoraroresuzor.pdfIn PDF document text
    • http://lignumweb.com/site/webroot/uploads/files/jutoperererugugitubaliw.pdfIn PDF document text
    • http://www.findvoters.com/userfiles/file/rakanutenek.pdfIn PDF document text
    • http://maturitni-ples.eu/UserFiles/File/wagemufuropofadumagizi.pdfIn PDF document text
    • http://hnsunnyfood.com/d/files/9423177883.pdfIn PDF document text
    • http://khiensa.com/UserFiles/File/44873618192.pdfIn PDF document text
    • https://www.bevillelecomte.ovh/ckfinder/userfiles/files/lajotoperufagemurur.pdfIn PDF document text
    • http://youngshiny.com/userfiles/file/1631312842.pdfIn PDF document text
    • http://nenkin-t.com/upload_img/ck/files/xenog.pdfIn PDF document text
    • https://satesayap.com/contents/files/bogenenusinefunex.pdfIn PDF document text
    • http://klccpa.com/userfiles/file/voguzakanadexerufupip.pdfIn PDF document text
    • http://rexant.by/upload/editor/files/wogofepudadamu.pdfIn PDF document text
    • http://baikalspring.ru/ckfinder/userfiles/files/xejurufanofagiwofi.pdfIn PDF document text
    • http://xecuoihuyhoang.com/uploads/userfiles/file/fedadolexiguwepid.pdfIn PDF document text
    • http://citty.org/images/uploads/file/34015500084.pdfIn PDF document text
    • https://democv.associasuite.com/imagenes/contenidos/files/27411123487.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_off0000b74a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB74A 16308 bytes
SHA-256: bfe7c9e37c19b2e8fb9bb0d0e4f8ad22f2ce5bae3873eb843f9e07e5c4599685
font_01_sfnt_off0000e132.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE132 10488 bytes
SHA-256: 4c1b660a307d1fba495cbf09db330af8d80305899225fa84bd50162ef03902bf
font_02_sfnt_off0000f93e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF93E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1