Malicious PDF — malware analysis report

Static analysis result for SHA-256 348c8b758f46781d…

MALICIOUS

PDF

73.9 KB Created: 2021-09-08 19:15:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 5e2779d28cf93599a74759627dd56823 SHA-1: d05136a792a3efecb1a34ba051de2aa53a0b8747 SHA-256: 348c8b758f46781dbca8e2f79783956eb272da1a5dc46b59023a44ca60c91b91
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, specifically identified as a phishing trojan by ClamAV. It contains a large number of embedded URLs, many pointing to compromised WordPress upload directories or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and unreadable, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://crewmak.ru/uplcv?utm_term=gulf+times+pdf+qatar PDF link annotation
    • http://zeci.nl/im/image/guvopejiniseral.pdfIn PDF document text
    • http://onthebroadway.com/CPD/adminpanel/upload/file/madisavimuket.pdfIn PDF document text
    • http://phanphoiongnhuahoasen.vn/upload/files/wakomuwajalomonelux.pdfIn PDF document text
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/16137738417a19---26348513888.pdfIn PDF document text
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/ba950c3117929781122cd1c8a61ade34/kejeliw.pdfIn PDF document text
    • http://hortherbpublisher.com/files/upfiles/file/50615885862.pdfIn PDF document text
    • http://logisticsnetworks.net/ckfinder/userfiles/files/19010792936.pdfIn PDF document text
    • http://mail-ex.net/userfiles/file/sigajupafo.pdfIn PDF document text
    • http://conditum.nl/userfiles/file/68015044613.pdfIn PDF document text
    • https://www.hdontheroadnapoli.it/wp-content/plugins/formcraft/file-upload/server/content/files/16130d05791d25---6643653658.pdfIn PDF document text
    • http://ceramvetro.net/userfiles/file/2846830832.pdfIn PDF document text
    • https://taiwancy.com/app/webroot/userfiles/files/gederameweduzaxi.pdfIn PDF document text
    • https://www.idd.no/ckfinder/userfiles/files/nuwefigu.pdfIn PDF document text
    • https://study-go.info/wp-content/plugins/super-forms/uploads/php/files/99590407e8c38c9989967b95a631d88a/gedolega.pdfIn PDF document text
    • https://satnamunicipalcorporation.com/admin/ckfinder/userfiles/files/demupixomimekew.pdfIn PDF document text
    • https://lifesmart.ro/ckfinder/userfiles/files/walisenepepanojataxow.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134d074f069e---ruduwinerusemexirobofawes.pdfIn PDF document text
    • https://telechips.com/ckfinder/userfiles/files/85670064340.pdfIn PDF document text
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1612f4545c7ada---81281972537.pdfIn PDF document text
    • http://thietbibepnhahang.net/media/files/69867432281.pdfIn PDF document text
    • https://www.educazionesessuale-scuola.ch/ck/ckfinder/userfiles/files/16136726358.pdfIn PDF document text
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/161380cfeb4aa0---96532587779.pdfIn PDF document text
    • http://como.gattinonimondodivacanze.it/themes/userfiles/files/48964787579.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_off0000bc22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC22 10720 bytes
SHA-256: b582535196366f8f9ec192a45ffa19b32e6d03c281c46176c4455e6ca0133a2c
font_01_sfnt_off0000d486.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD486 17572 bytes
SHA-256: 90b9cc4753a339baf560336919d9b32c7a1d77ef49f8ad947fff05eb3e93c688
font_02_sfnt_off00010256.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10256 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1