Malicious PDF — malware analysis report

Static analysis result for SHA-256 613f57268dbb8117…

MALICIOUS

PDF

86.8 KB Created: 2021-09-12 10:48:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: ec9cca2085725f39964dc7a9c136ff2e SHA-1: ddc05cc50770d778ad1fe448d38cd68bda8f7d20 SHA-256: 613f57268dbb81172048d6ab27a37f48ae067401296ac82700985fb7a45bb9a3
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to various domains, likely intended to obscure the final destination and evade detection. The presence of multiple compromised CMS upload links further supports a malicious intent to host or distribute further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://goooinggroup.com/userfiles/files/20210906_011150.pdf In PDF document text
    • https://skinrepublic.vn/webroot/img/files/82118259298.pdfIn PDF document text
    • http://goodtraefarm.com/ckupload/files/21811907041.pdfIn PDF document text
    • http://dworbieland.pl/userfiles/file/16650301006.pdfIn PDF document text
    • http://wxmx.cn/upload/ckimg/files/202109112051533055.pdfIn PDF document text
    • http://casier-a-bouteilles.com/file/musopu.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131f290b831b---2389992232.pdfIn PDF document text
    • https://kiptep.ru/file/58791258390.pdfIn PDF document text
    • http://blekinge.boj.se/uploads/userfiles/files/lamasidabunudelemujogika.pdfIn PDF document text
    • http://dulichtantai.com/files/uploaded/files/podejigaxi.pdfIn PDF document text
    • http://st-johnson.com/Uploadfiles/files/nozexosomepav.pdfIn PDF document text
    • https://boucherienabli.com/uploads/FCK_files/file/funesejixewoz.pdfIn PDF document text
    • http://artdealer.vn/upload/fckimagesfile/eb48699de2fd0ca20414059eaa36c75f.pdfIn PDF document text
    • http://i-tos.com/userData/board/file/sijazajakovigize.pdfIn PDF document text
    • http://freemansphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134531ea5d76---65772703224.pdfIn PDF document text
    • http://balbu.hu/uploads/news/file/98063930996.pdfIn PDF document text
    • https://sibservis.com/ckfinder/userfiles/files/33399325980.pdfIn PDF document text
    • https://zebcom.in/userfiles/file/jedesilipogog.pdfIn PDF document text
    • https://sedefartphotography.com/resimler/files/memerejajirizenipogo.pdfIn PDF document text
    • https://toliveinchristjesus.ceosale.catholic.edu.au/application/third_party/ckfinder/userfiles/files/kajasazaju.pdfIn PDF document text
    • http://market-oborudovanie.ru/upload/file/77562298573.pdfIn PDF document text
    • http://melabo.com/upload/files/86540197374.pdfIn PDF document text
    • http://buyyoutubesubscribers.com/ci/userfiles/files/rupifera.pdfIn PDF document text
    • http://hangquangauto.com/files/87699373224.pdfIn PDF document text
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/6ju4sfkn6tgllpuhdgrgoeead1/1953514292.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=android+auto+screenshotPDF 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_off0000edb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDB8 18128 bytes
SHA-256: a3262b0723e434dd6630d10182e50e1c0cb878d5129f96af75dc9f039a78b576
font_01_sfnt_off00011d3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D3E 10500 bytes
SHA-256: 13037746974f29a4a64a9b09e7f1dc6d2cb412dbceb0bb5e6161b6e64183fcc0
font_02_sfnt_off00013520.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13520 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1