Malicious PDF — malware analysis report

Static analysis result for SHA-256 d39f2767c2f877b0…

MALICIOUS

PDF

84.4 KB Created: 2021-09-09 19:02:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 13f4699e7f4a8d41cd4201ab100e9f2f SHA-1: d05c46b85029e8bdb00a6d4b0f0724f9171ab527 SHA-256: d39f2767c2f877b05a1a7a09d08537357b7f516bea9232d6584a1314fe893e32
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised WordPress upload directories, suggesting it's part of a link farm designed to host and distribute malicious files. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution. While no scripts were directly extracted, the PDF structure and URL patterns are consistent with techniques used to deliver second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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 http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/16132d8a7613b2---ludaxaziw.pdf In PDF document text
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137e41043f1e---buzamoxavojoda.pdfIn PDF document text
    • http://ryukatsu.com/userData/board/file/dosivaxaxavebuvise.pdfIn PDF document text
    • https://cobaltinc.org/userfiles/file/1223443571.pdfIn PDF document text
    • https://ku4ysk-9lgp4y.com/contents/files/sosikapozenedejo.pdfIn PDF document text
    • https://papiratisk.cz/soubory/47736354590.pdfIn PDF document text
    • http://palyavalaszto.hu/teszt/upload/file/gunefil.pdfIn PDF document text
    • http://boldino-hotel.com/ckfinder/userfiles/files/3727142180.pdfIn PDF document text
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/1613249f3a8fc3---silajizenogifudawuvuji.pdfIn PDF document text
    • https://ckeditor.pamlskovnik.cz/ckfinder/userfiles/files/xovinaxeforuxilofomakij.pdfIn PDF document text
    • https://agrocare.ro/ckfinder/userfiles/files/2245568845.pdfIn PDF document text
    • https://ultralloy.net/upload/files/nezaragugilusabusi.pdfIn PDF document text
    • http://jjburgerut.com/uploads/files/65100149037.pdfIn PDF document text
    • https://equinox-e.com/upload/files/wifajuzoli.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/38f21f790f9d2c266baf9fac662c2377/22856073454.pdfIn PDF document text
    • http://gatewayhotelbangkok.com/upfile_hotel/files/misefikezusifuxo.pdfIn PDF document text
    • https://berbagiangka.com/contents/files/86025802468.pdfIn PDF document text
    • http://pnalog.ru/images/file/kugadojodepigola.pdfIn PDF document text
    • http://lnaixi.com/userfiles/file/20210902050353_1658564135.pdfIn PDF document text
    • https://magerp.org/upload/files/jajisejawona.pdfIn PDF document text
    • https://chinese-wall.tw/upload/files/wevimoreti.pdfIn PDF document text
    • https://studio45.live/wp-content/plugins/super-forms/uploads/php/files/cilp6gapoi2tioualhmjm0esq0/22575028299.pdfIn PDF document text
    • http://surmounttravel.com/userfiles/files/58803026132.pdfIn PDF document text
    • https://dhins.com/testingsites/advantage_aviation/assets/media/file/16112332349.pdfIn PDF document text
    • https://clearpatth.com/userfiles/file/82515728584.pdfIn PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1613767eb30ce4---28741766009.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=flight+download+apkPDF 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_off0000e2f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2F5 19256 bytes
SHA-256: 0206576a2323b25747d5a2d8994bd18d42bd96c267526a5eb0c4dbeb7a3c2424
font_01_sfnt_off000114cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114CD 10424 bytes
SHA-256: 8bc00ad73f1024703764a9f8560f7772638383f69dfc68d9fbe9a14a5dd58359
font_02_sfnt_off00012c26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C26 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1