Malicious PDF — malware analysis report

Static analysis result for SHA-256 e237b32743edbcd7…

MALICIOUS

PDF

84.7 KB Created: 2021-09-16 23:02:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 83acb99ef2be1b8a75f7c7553619c1bd SHA-1: 051cb6f2d8609ec338594f87e3a1a2207758428a SHA-256: e237b32743edbcd77fb22cc39d62101f19cdb5f3ba0b18c8f473c32e6484efd5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The 'wkhtmltopdf' authoring application and the presence of embedded URLs indicate a likely intent to deliver a second-stage payload or phish credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://ketchas.ru/uplcv?utm_term=barometer+apps+android PDF link annotation
    • https://sandipkumardutta.com/ckfinder/userfiles/files/jegajigumebulasufes.pdfIn PDF document text
    • https://nawaasha.org/userfiles/file/kodinolovojemom.pdfIn PDF document text
    • https://delphin-bau.com/ckfinder/upload/files/janigusul.pdfIn PDF document text
    • https://dukupahit.com/contents/files/45368125170.pdfIn PDF document text
    • https://fnb-concepts.com/images/uploads/files/43409605778.pdfIn PDF document text
    • http://plenaseguroseprevidencia.com/fotosempresa/files/zewadeke.pdfIn PDF document text
    • https://apexsafetyproducts.com/ckfinder/userfiles/files/wojegoxesan.pdfIn PDF document text
    • https://dnmpaint.com/sdcc/images/file/70476732762.pdfIn PDF document text
    • https://sharidendesignasphalt.com/wp-content/plugins/super-forms/uploads/php/files/6f490581c2352027934798349d23d246/91869186352.pdfIn PDF document text
    • http://gadkowski.pl/repository/filemanager/file/70218588819.pdfIn PDF document text
    • https://www.webhisto.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613bd8c905f85---wakabudug.pdfIn PDF document text
    • http://21cedu.com/pds/userfiles/files/sitozozurej.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/16133e3053f6d8---dakekoso.pdfIn PDF document text
    • http://thepokewave.com/uploads/files/rebixujesobazamuziga.pdfIn PDF document text
    • https://etre-cheval.fr/Applications/MAMP/htdocs/etre%20cheval/news_pix/file/10748276012.pdfIn PDF document text
    • http://101-games.ru/images/uploads/files/29305045349.pdfIn PDF document text
    • http://stonebreaker.at/tamov.pdfIn PDF document text
    • http://www.dreamstoreonline.es/ckfinder/userfiles/files/figukamijeg.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/16135088657242---67827664374.pdfIn PDF document text
    • https://bestcaps99.com/ckfinder/userfiles/files/labizivoveso.pdfIn PDF document text
    • http://pantipplaza.com/userfiles/file/xopoverafezu.pdfIn PDF document text
    • http://cephedanismani.com/images/pages/file/feruju.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_off0000e84d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE84D 17640 bytes
SHA-256: 7f05e96a884b8b076937b7f1259e76a21bdb5f2bfa6e141cab418257606e62dc
font_01_sfnt_off0001156c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1156C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012d83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D83 10560 bytes
SHA-256: c407cfe7eb23bbe66c172fbc978ba5b1d95786fe1f46cc1779398a66a0105ac7