Malicious PDF — malware analysis report

Static analysis result for SHA-256 de8bb506c6bf0b35…

MALICIOUS

PDF

80.9 KB Created: 2021-09-18 16:43:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 90b06693e4a49b46b4e296111ad7cf12 SHA-1: 57a38ab05bff1c4ce08efb51a2524fab90c1a6dd SHA-256: de8bb506c6bf0b358b993ce10457bb40aadf0f44aed73b0e89890095b9b37457
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV. It contains numerous links to external websites, many of which are hosted on compromised or disposable domains, suggesting a link farm or phishing lure. The presence of PDF-specific heuristics like 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this, indicating the PDF is designed to redirect users to potentially malicious content. No scripts were extracted, but the overall structure points to a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://alebusph.centralcms.cloud/galeria/files/12350150850.pdf In PDF document text
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1612fcd17bfa10---vodojutib.pdfIn PDF document text
    • http://chukysovin.com/img-svc/files/wutasibijarinorizanu.pdfIn PDF document text
    • http://www.letnifestiwal.pl/ckfinder/userfiles/files/95123112261.pdfIn PDF document text
    • http://saothienemb.com/uploads/images/files/podiwim.pdfIn PDF document text
    • https://jv-cms.crazy-jessie.nl/uploads/files/64309423133.pdfIn PDF document text
    • https://smartstone.ca/userfiles/files/87284611260.pdfIn PDF document text
    • http://litroshaber.net/resimler/files/redolutof.pdfIn PDF document text
    • http://xn--knstlerische-biografie-arbeit-lbd.ch/userfiles/files/demezexavupilepavim.pdfIn PDF document text
    • http://ptaki.info/imgekoprojekty/files/siligisajelafubokasakekev.pdfIn PDF document text
    • http://yidaig.com/uploadfile/file/20210916045200.pdfIn PDF document text
    • https://sanaspinler.com/calisma2/files/uploads/pidasuwajoterumu.pdfIn PDF document text
    • https://abhrian.com/userfiles/files/ludobariwoware.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/rlvj58ct84napsuvelkm5gbffg/nepugejibaguz.pdfIn PDF document text
    • https://www.intermediastudios.com.mx/wp-content/plugins/super-forms/uploads/php/files/44bc4c22c5dd8aa203e10cfa0fb22580/neripitakit.pdfIn PDF document text
    • https://afmiletisim.afmiletisimajansi.info/resimler/files/babevivimelilisedubopajuv.pdfIn PDF document text
    • https://amursvoidom.ru/media/files/jatuluzofizaninapape.pdfIn PDF document text
    • https://tidaksusah.com/contents/files/tuzimufol.pdfIn PDF document text
    • http://pomocnaukowa.net/Upload/file/23310391635.pdfIn PDF document text
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/161445e90bd841---bagifixununutepedu.pdfIn PDF document text
    • https://ozora.schaffsen.com/contents/file/47582513602.pdfIn PDF document text
    • https://personalloan2u.com/wp-content/plugins/super-forms/uploads/php/files/459a56ac62d5c9eb9e0627eb9a9c68a5/rukolijusefabeziwazavepu.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/16138ba26863fc---30143384304.pdfIn PDF document text
    • http://cnsgawefgl.netsociality.com/upload/files/wedobopedulu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=how+to+install+modded+play+storePDF link annotation
    • 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_off0000d8f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8F5 10744 bytes
SHA-256: b97f69f02baece0cadd5f280fbd3c65ee3b634312527aa6109f3d8e1c6d4f77c
font_01_sfnt_off0000f1a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1A4 17276 bytes
SHA-256: ba6f6dc83dd22df66a21d78b77b97b3005fbf2fff6185d22e6adf8abc682d768
font_02_sfnt_off00011e36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E36 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1