Malicious PDF — malware analysis report

Static analysis result for SHA-256 b645b372ba336e5d…

MALICIOUS

PDF

72.5 KB Created: 2021-09-14 00:52:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 35a6c7426e0e018e0a99169c02d4c204 SHA-1: fd4c4134b507c534506445774ac95007db640db7 SHA-256: b645b372ba336e5dffa215a464af8d5607a163de355f106b69c52e1f7eb4f4b7
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are hosted on suspicious domains and appear to be part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were directly extracted, the PDF structure and URL distribution suggest it's used to redirect users to malicious sites, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9915

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://bwawarszawa.pl/upload/file/midavumizeronemujalefik.pdf In PDF document text
    • http://bpabv.nl/uploadfiles/file/wavuzufotof.pdfIn PDF document text
    • https://ooobelkom.ru/ckfinder/userfiles/files/sobugumewefevajaz.pdfIn PDF document text
    • http://sitoad.com/bbqjoekey/files/202109032007409200.pdfIn PDF document text
    • https://taiwancy.com/app/webroot/userfiles/files/dogaj.pdfIn PDF document text
    • https://soportedevida.mx/ckfinder/userfiles/files/sejuniwijeribevusenaritot.pdfIn PDF document text
    • https://camphacement.vn/upload/files/tewedaz.pdfIn PDF document text
    • http://24hnbc.com/assets/ckfinder/core/connector/php/uploads/files/46300092725.pdfIn PDF document text
    • https://ddnepal.com/assets/userfiles/files/53542444132.pdfIn PDF document text
    • http://worldprint.su/userfiles/file/jerewizifuwejamixazev.pdfIn PDF document text
    • https://himalayanwanderer.com/himalayan/userfiles/files/gudibefadixibapebe.pdfIn PDF document text
    • https://kp-bs.ru/upload/files/64495894642.pdfIn PDF document text
    • https://bliznacite.com/files/53369478532.pdfIn PDF document text
    • https://ecoinkworld.com/wp-content/plugins/super-forms/uploads/php/files/0bf59b14c6923074e45c7706f8c25f4e/13942440615.pdfIn PDF document text
    • http://xn--82cac8d3ajrc0gd0bo4a7nf3qg.com/userfiles/files/1185858707.pdfIn PDF document text
    • https://alves.bg/ckfinder/userfiles/files/48059642432.pdfIn PDF document text
    • https://www.delaneyllc.com/ckfinder/userfiles/files/44250711975.pdfIn PDF document text
    • http://thriftstorewebsites.net/flash/thriftstorewebsites.net/file/vimevapegakib.pdfIn PDF document text
    • http://brighterhealthcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/7g8p46jk2nlchsmr58sft9qnkr/niwajovetawe.pdfIn PDF document text
    • http://suliaok.com/v15/Upload/file/202195197148858.pdfIn PDF document text
    • http://ceskylakros.cz/userfiles/file/3839620663.pdfIn PDF document text
    • http://katela.net/userData/board/file/70651593231.pdfIn PDF document text
    • http://enewind.com/pliki/file/30544808290.pdfIn PDF document text
    • http://bakefruit.com/uploads/files/202109080021273866.pdfIn PDF document text
    • http://turnwealthy.com/ckfinder/userfiles/files/masus.pdfIn PDF document text
    • https://www.scmsgroup.org/ckfinder/userfiles/files/dimegaxijadikiruzofaxovoz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=all+star+tower+defense+how+to+tradePDF 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_off0000b94c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB94C 16656 bytes
SHA-256: 5930fa51182fb00e9ef4e759062c9eda3b610c9e57c873f1c28c2e6b1b65356e
font_01_sfnt_off0000e42b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE42B 10424 bytes
SHA-256: ca6e67c2764746200a9a1e3dbe6daba50bcf80c000f3d58532dd4527f53a1129
font_02_sfnt_off0000fbdc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBDC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1