Malicious PDF — malware analysis report

Static analysis result for SHA-256 91990de7ebbfd610…

MALICIOUS

PDF

69.3 KB Created: 2021-09-27 10:50:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 5fbbf7257068b7e294a39ce6289c0948 SHA-1: f25e52b964b43e81b91991da76578d01685576d1 SHA-256: 91990de7ebbfd610f81233e72bd0b72aed0b7eb2e89988658e346a33c2ace03f
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was identified as malicious by ClamAV and an ML classifier, with critical and high severity firings. It contains embedded JavaScript, which is often used to exploit PDF vulnerabilities or redirect users. The PDF also exhibits characteristics of a link farm, with numerous external URLs pointing to potentially malicious content, indicating a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://limsurdua.com/contents/files/95385606382.pdf In PDF document text
    • https://weboonline.com/ckfinder/userfiles/files/56577115053.pdfIn PDF document text
    • http://golden-candies.ru/webroot/files/files/lupanabejovuketabigizewa.pdfIn PDF document text
    • http://haliburtonhighlandsheritage.ca/userfiles/file/lejetugokalejel.pdfIn PDF document text
    • http://aggengr.com/uploads/CMS/file/11969050197.pdfIn PDF document text
    • http://coutleelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/rexawuno.pdfIn PDF document text
    • http://petraifevronii.ru/ckfinder/userfiles/files/49130669435.pdfIn PDF document text
    • http://cowmoo.org/ckfinder/userfiles/files/xojujasabibiruzonit.pdfIn PDF document text
    • http://anipetkingdom.com/webroot/img/files/11043029027.pdfIn PDF document text
    • http://adveotec.com/img/file/sogik.pdfIn PDF document text
    • https://rozynoklinika.lt/userfiles/file/1254192609.pdfIn PDF document text
    • https://agrocare.ro/ckfinder/userfiles/files/daduxenijageromivebele.pdfIn PDF document text
    • http://cellfruits.com/ckfinder/userfiles/files/liwesidigitapinifarokuke.pdfIn PDF document text
    • http://stcforanebanglore.smcim.com/www/js/ckfinder/userfiles/files/maxiberamalunidudi.pdfIn PDF document text
    • http://plantessentialoil.com/upload/files/gufoxaviwirewuwawaluwopop.pdfIn PDF document text
    • https://nasikampung.info/contents/files/94510222926.pdfIn PDF document text
    • https://highrise.pl/file/luturujekulerobimakuwak.pdfIn PDF document text
    • http://toyotarent.tw/FileData/ckfinder/files/20210922_BE7731EE9AB7E275.pdfIn PDF document text
    • http://woodbridgeabw.com/uploads/files/zalilo.pdfIn PDF document text
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613dd9e0de61d---75005262509.pdfIn PDF document text
    • http://xn----7sbjvweekof5d.xn--p1ai/files/files/lomaxo.pdfIn PDF document text
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/161477919ab118---gemepezodedonigiliwuxofi.pdfIn PDF document text
    • http://jingmingtai.com/filespath/files/20210901120158.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=best+android+text+editorPDF link annotation
    • http://e1pl2.nazwa.pl/busy/fotki/file/34261856442.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_off0000b2f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2F5 10348 bytes
SHA-256: 70883251b3a0004fc0fca879126e5e563d47686bb84a980cd12ef999677272cf
font_01_sfnt_off0000ca86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA86 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e298.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE298 14688 bytes
SHA-256: 834cd3c38f568dde1c1d108454deb6eef81af63024b7364137de937403b083e9