Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f2e9ebf1faa8239…

MALICIOUS

PDF

81.5 KB Created: 2021-09-16 22:02:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fd0069a4316f6250f06ee90f5b3506ca SHA-1: be8b91139422900a7f4f4adaa690d04686b66fd9 SHA-256: 8f2e9ebf1faa82390d875ab4f020be49f811242eeeda3ba470a7267ee8138dae
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file is a PDF identified as malicious by ML classifiers and ClamAV. It functions as a link farm, containing numerous URLs pointing to various domains, many of which appear to be compromised or disposable hosting. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics indicates a deliberate attempt to obscure the final destination or leverage compromised infrastructure. The primary attack pattern is likely to lure users into clicking these links, potentially leading to phishing sites or malware downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9944

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://ismet.com.br/ckfinder/userfiles/files/nidudajufebepoli.pdf
    • http://dietetyka-24.pl/images/files/19981213778.pdf
    • http://asja-doll.ru/userfiles/file/71109831736.pdf
    • http://chafewyuok.handysociality.com/upload/files/totexatibisakuxel.pdf
    • https://myclubowners.com/userfiles/files/sobanogoxokefu.pdf
    • https://deshpanday.com/ckfinder/userfiles/files/demasujasozivepil.pdf
    • http://uspeh-kursk.ru/ckfinder/userfiles/files/72038328638.pdf
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142b5213b7f8---gewojobifab.pdf
    • http://hobbes-group.com/upload/files/jadidakapovizoxujox.pdf
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1612f30f7ba797---90015531224.pdf
    • http://komputerzagrosze.pl/userfiles/file/85498938103.pdf
    • https://promenade-perpignan.com/userfiles/file/lanavedifej.pdf
    • http://giorgimpianti.com/userfiles/file/pinojinagopigoforofedifus.pdf
    • http://christopherspubandgrille.com/userfiles/files/7199371173.pdf
    • https://vresponse.net/userfiles/file/2903623863.pdf
    • http://paoladebenedetti.eu/userfiles/files/5918380824.pdf
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613f702a6f376---13623433096.pdf
    • https://holocaustresearch.pl/nowy/photo/file/26545328316.pdf
    • http://geodeslaboratori.eu/userfiles/files/14614314601.pdf
    • http://vstarmp.cn/upload/files/20210905_141647.pdf
    • http://maiodi.com/userfiles/files/rolidovuxutajaxomelunos.pdf
    • http://risorsaterra.it/userfiles/files/mezurakozomivig.pdf
    • http://interroadholland.nl/userfiles/file/witexejimedunemufo.pdf
    • https://afma.pt/site/upload/file/98998278597.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=rich+dad+poor+dad+pdf+free+download
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off0000c16c.bin
947c2b9e9a7a56d5008cc70e80613e51a5d8ec8bd01053226404353db66d4925
decompressed-pdf-stream PDF FlateDecoded stream at offset 0xC16C 17476 bytes
font_01_sfnt_off0000dbd6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDBD6 16792 bytes
font_02_sfnt_off0000f3ed.bin
e52fc711dff6bdf0238a5237b8869003a3cac817eeb2f30b7c3d312556056462
pdf-font-stream PDF embedded font (sfnt) at offset 0xF3ED 10584 bytes
font_03_sfnt_off00010c09.bin
e7b503d3cdd4152243fb803bc9489fe05167863bf6d448255ca8912ffb9a9923
pdf-font-stream PDF embedded font (sfnt) at offset 0x10C09 16780 bytes