Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c368c5fc78c5ca8…

MALICIOUS

PDF

76.7 KB Created: 2021-09-03 08:28:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 8a7cca2353a5aa905fc78769771c30fd SHA-1: b9d4e35cc369ca0e5a9bb341c65b65dc491ebb13 SHA-256: 3c368c5fc78c5ca8411e72f0896d23a8a41c533e81ffd33ade274225f4b55fac
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, containing numerous URLs pointing to compromised WordPress sites and disposable hosting, likely intended to redirect users to malicious content or phishing pages. The presence of multiple external URIs and link farm heuristics strongly suggests an attempt to lure users to external, potentially harmful, resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://cructi.ru/uplcv?utm_term=manual+unidad+de+cuidados+intensivos+pdf PDF link annotation
    • http://kcobafl.org/ckfinder/userfiles/files/xilamovimopagev.pdfIn PDF document text
    • http://itaindustrial.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609a1c70802f7---40887776252.pdfIn PDF document text
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e7b9aeb034---pubesane.pdfIn PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/omo3r9ja2tpsc54cm24unk8kce/nelirefenetaba.pdfIn PDF document text
    • http://dinskayarealty.ru/media/file/62356939188.pdfIn PDF document text
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/2ohdvtf5955t0u740ls4detss2/kupimaxin.pdfIn PDF document text
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf97135cfb1---66165137449.pdfIn PDF document text
    • http://aodaibooking.com/FileData/ckfinder/files/20210614_215F333976BF24DA.pdfIn PDF document text
    • https://zoomkish.com/basefile/zoomkishcom/files/32504022572.pdfIn PDF document text
    • http://beadsandsupplies.com/images/file/94015709323.pdfIn PDF document text
    • http://melvin.cz/data/76313445909.pdfIn PDF document text
    • http://podlahypilat.cz/admin/file/lujisefap.pdfIn PDF document text
    • http://turningpointdigital.com/cote_dor_import/admin/ckfinder/userfiles/files/87075179333.pdfIn PDF document text
    • https://vietfun.com.vn/wp-content/plugins/super-forms/uploads/php/files/h9207j0npo6a1vqi86g1frl91d/teruxurutugorovab.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/wuzovoxosu.pdfIn PDF document text
    • https://mls.lighting/wp-content/plugins/super-forms/uploads/php/files/90bb38c4e42cb0354fb08089a509e25b/webex.pdfIn PDF document text
    • https://www.twibiotech.com/plugin/ce1/ckfinder/userfiles/files/fevodamemawejozopufowafu.pdfIn PDF document text
    • http://studiogallerani.it/userfiles/files/vazejinafof.pdfIn PDF document text
    • http://sapaelitehotel.com/webroot/img/files/22618093252.pdfIn PDF document text
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/7qeoi1tl9kbffethol7858jf5l/gatewewurozelisiwexej.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/c008cfe44fcc6acbef9d63efb63ad1d3/tugamolowelatibavokazemo.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_off0000c38f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC38F 19260 bytes
SHA-256: 6ee14db68e438f3a9081de98b84874f598c96698683573a5c8319e6f0bd4cd77
font_01_sfnt_off0000f498.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF498 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010caf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CAF 10672 bytes
SHA-256: e4c5c1b2ac9f0177eba0effbdea96dec79eb23df7c79707d94f65104360f8ee0