Malicious PDF — malware analysis report

Static analysis result for SHA-256 deb933f23dffb15f…

MALICIOUS

PDF

91.8 KB Created: 2021-09-22 09:44:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 0c428e53a3822f81ef855b7e335c1eae SHA-1: fd35754f7a3fd04140f59328849b1079f11ed690 SHA-256: deb933f23dffb15fcc37c4a769ebced1a0876672cc750d6221abbd9625b7e40a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. The presence of multiple external URIs and compromised CMS upload links supports the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://pistant.ru/uplcv?utm_term=griffiths+introduction+to+quantum+mechanics+solutions PDF link annotation
    • https://sindhuinvestment.com/ckfinder/userfiles/files/gofukebinenikemen.pdfIn PDF document text
    • http://aci-immobilier-douai.fr/userfiles/files/83509423402.pdfIn PDF document text
    • http://studioferrato.it/userfiles/files/gazuba.pdfIn PDF document text
    • http://nbc.com.vn/ckfinder/userfiles/files/29682702944.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613c1cadc45dd---fujipukemezasamidumuva.pdfIn PDF document text
    • https://razredna-nastava.net/files/jejoretesijolomeri.pdfIn PDF document text
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/161378f274c8c9---dotixosuzisaliboj.pdfIn PDF document text
    • http://mcap.cz/images/uploadedimages/file/53177494203.pdfIn PDF document text
    • https://monyetmesum.com/contents/files/39996107612.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/161430bd19c6d7---78611348849.pdfIn PDF document text
    • https://office-agglo-larochelle.fr/userfiles/file/86554443484.pdfIn PDF document text
    • http://xn--80aaffebba2apgigwiiececnggk9e4k.xn--p1ai/pict/file/sabetigenigatowebitewame.pdfIn PDF document text
    • http://dailyliving.nl/ckfinder/userfiles/files/19828025811.pdfIn PDF document text
    • http://palakkadtourism.in/ckfinder/userfiles/files/59773311313.pdfIn PDF document text
    • http://meta-min.com/files/68638465688.pdfIn PDF document text
    • http://lilit-realty.com/wp-content/plugins/super-forms/uploads/php/files/u2v0iopgkdptsco87n412it8g1/vesabokizijogevenipujo.pdfIn PDF document text
    • https://theatresaucinema.fr/uploads/file/5124248588.pdfIn PDF document text
    • http://elfuklid.cz/foto/Image/file/bixetinupikerezugu.pdfIn PDF document text
    • http://mebco.ru/images/file/xazujenepekabepitof.pdfIn PDF document text
    • http://degeninhotel.ru/admin/ckfinder/userfiles/files/16057164786.pdfIn PDF document text
    • http://daehnfeldt.com/userfiles/file/98779453263.pdfIn PDF document text
    • http://www.waetsukai.jp/system/ckfinder/userfiles/files/15865618760.pdfIn PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/16143da10be8c6---kasiv.pdfIn PDF document text
    • http://nepodoshlo.kz/ckfinder/userfiles/files/93546671972.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_off0000f463.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF463 11024 bytes
SHA-256: 2908c7f9ef3bb0e92786ffc4a2e18ff104a50a2eff02259562912cd9e6215935
font_01_sfnt_off00010da7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DA7 22600 bytes
SHA-256: d2e80590f0de23179e54255ca312de28be2deeeb969f886acdf84a4a014174ab
font_02_sfnt_off000148d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x148D5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1