Malicious PDF — malware analysis report

Static analysis result for SHA-256 f74ad2b5268f5424…

MALICIOUS

PDF

76.4 KB Created: 2021-09-19 16:54:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 38509d3162415f11af9d7ef2c7add6b4 SHA-1: b464636dbbfd3534f018206c3f06618ae8245b3a SHA-256: f74ad2b5268f542475c4092fed6574c518e9d930f62c859fb797b1bdfcc5eb8d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which are hosted on disposable domains and appear to be part of a link farm, suggesting a phishing or malware distribution scheme. The presence of PDF-specific heuristics like PDF_SEO_DISPOSABLE_LINK_FARM further supports this conclusion.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://cructi.ru/uplcv?utm_term=nfs+offline+apk PDF link annotation
    • http://dlshixiang.com.cn/ckfinder/userfiles/files/4294365398.pdfIn PDF document text
    • http://phutunggiahungoto.com/uploads/files/kewawilidibo.pdfIn PDF document text
    • http://dush-kz.ru/uploads/fck/file/52419014657.pdfIn PDF document text
    • http://koala-al.com/d/files/tatavuvibis.pdfIn PDF document text
    • http://kanalizace-ul.cz/userfiles/file/mimobanutidir.pdfIn PDF document text
    • http://alianzablue.com/aym_image/files/fejamo.pdfIn PDF document text
    • http://kammatrans.com/userfiles/files/27940268601.pdfIn PDF document text
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/16135afe2bf0c1---34246150935.pdfIn PDF document text
    • http://innotec-industrie.be/userfiles/file/19875463276.pdfIn PDF document text
    • http://escuelasfutbol8.com/docs/files/gemuxadevovawisadarakus.pdfIn PDF document text
    • https://prestinieurope.com/userfiles/files/wimoragesapavoruloruwubab.pdfIn PDF document text
    • http://chekeeh.ir/basefile/chekeehir/files/59238884105.pdfIn PDF document text
    • https://portugaliaimagyarok.com/ckfinder/userfiles/files/nowowu.pdfIn PDF document text
    • http://www.pantonerestauri.com/ckfinder/userfiles/files/deralotagazuzipadumoga.pdfIn PDF document text
    • http://dreamcatcherltd.com/userfiles/file/56518144723.pdfIn PDF document text
    • https://zippy-inc.com/app/webroot/userfiles/files/11885742063.pdfIn PDF document text
    • http://talesma.com/E/file/83595211849.pdfIn PDF document text
    • http://simkoongschool.com/uploads/editer/files/37441694928.pdfIn PDF document text
    • http://open.ua/uploads/ckeditor/files/8904689686.pdfIn PDF document text
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613107888b474---86822534760.pdfIn PDF document text
    • https://aldapa.eus/files/galeria/files/83370994411.pdfIn PDF document text
    • https://aldapa.eus/files/galeria/files/jalukeseropikeli.pdfIn PDF document text
    • https://hanomanberjaya.com/contents/files/nubasumuwazepozuxoli.pdfIn PDF document text
    • https://natinsel.com/imagenes/file/95251431996.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_off0000c9ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9ED 16796 bytes
SHA-256: b74d336d183dc66d0736e51eae9f4cbed67c1ecfdb6eb673dbe52e25c1508e81
font_01_sfnt_off0000f57e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF57E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010d95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D95 10220 bytes
SHA-256: cada71e0f0a3be068687873f4a695fbc4670135bdee8279be1b9e7f14432787d