Malicious PDF — malware analysis report

Static analysis result for SHA-256 a71f1518b5b12ccc…

MALICIOUS

PDF

79.9 KB Created: 2021-09-04 00:26:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7638a611061a4974a8b9281924cf0e17 SHA-1: 6cd2b80f504571e54b37b3674e4839d04807ed92 SHA-256: a71f1518b5b12ccc460e273518bea4fdfb56575e38704ff9e6f32056307885cf
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to deliver second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/96626bbbe33f18c50212bf3281e19ed8/92378455084.pdf
    • http://atek-ent.com/upload/file/zagemezel.pdf
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/16095519f12197---13369346513.pdf
    • http://tc-muehlacker.de/data/tcmuehlacker/userfiles/file/41809494254.pdf
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/9b775c69de7754cddadf46e93bc6b260/govepaw.pdf
    • http://artistalexanderkanevskyroyalshakespeareglobetheatrelondon.com/clientMedia/file/wegoxuranarivuzad.pdf
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/b3bc49a79cdf36961103e85a092b5b33/wimilazixesunomanulijo.pdf
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/160c2dd4171938---87958595627.pdf
    • http://ctkupavna.ru/upload/file/77422304451.pdf
    • http://kasystemofkarate.com/clients/861259/File/nezapevesasibudo.pdf
    • https://vuaship.com/wp-content/plugins/super-forms/uploads/php/files/1hpmtuj2r8a0b595a3omepaeef/pazufuwubimuwowaluxuv.pdf
    • http://www.kymenhome-etsinta.net/tiedostot/files/80497750711.pdf
    • https://www.sevgiliyevideo.net/wp-content/plugins/formcraft/file-upload/server/content/files/160cc68e6de31b---zedelekokoxokilobe.pdf
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160bb607e49262---63186928166.pdf
    • http://arredamentoambienti.it/img/file/nolagiputiraxaziwirepoz.pdf
    • https://amd-export.com/site/upload/file/89500108350.pdf
    • http://veewood.com/file_media/file_image/file/48939971629.pdf
    • http://btc-ltd.com/upload/file/gufupulunuzerebiki.pdf
    • https://pharma-tools.eu/galeria/file/tamijowi.pdf
    • https://dentalrud.com/userfiles/file/fagaxajida.pdf
    • http://doer-sh.com/Uploadfiles/files/motelagewon.pdf
    • https://muachungbaohiem.com/uploads/userfiles/file/nijonasajevixupoz.pdf
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/ci49bp021fjmeepf76nj4er5m0/5368700462.pdf
    • https://nmg.lv/img/uploads/files/81815120617.pdf
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609088ea2dd84---xenixupinuxebofa.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=encrypting+adobe+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d4c1.bin
cbc636e184175476e9d7e1763cb0935f01cd7d1fb9cf99ad7d88f2d9b3852b05
pdf-font-stream PDF embedded font (sfnt) at offset 0xD4C1 17168 bytes
font_01_sfnt_off00010173.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10173 16792 bytes
font_02_sfnt_off0001198a.bin
bf892e112a8119b249e50a62c8ea27227eb0d665352a20febe94449b30090a7f
pdf-font-stream PDF embedded font (sfnt) at offset 0x1198A 10816 bytes