Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7d7d9e1cc890e8c…

MALICIOUS

PDF

78.8 KB Created: 2021-09-16 23:48:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 2067cf6336ea6d4728dcebdf4d60032e SHA-1: 27b21f568e91da51c4c244725698553c6259a6e3 SHA-256: b7d7d9e1cc890e8cbfc4bc1876cdc53e77fc15aa1c893ed92c08789dd3c6cec8
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, with heuristics indicating embedded JavaScript and a link farm structure. The numerous external URIs point to a likely phishing or malware distribution scheme, leveraging disposable hosting. The embedded JavaScript is likely used to redirect users to these malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://catamma.ru/uplcv?utm_term=how+to+use+hdr+mode+on+android PDF link annotation
    • http://geoodwierty.pl/files/file/75897139101.pdfIn PDF document text
    • https://www.shipgo17.com/plugin/ckeditor/ckfinder/userfiles/files/zepivajinaniv.pdfIn PDF document text
    • http://t-p-fortune.com/userfiles/file/lesogufokusaxugo.pdfIn PDF document text
    • https://cvconstructionsgoa.com/pharma/admin/userfiles/file/sumaram.pdfIn PDF document text
    • http://wxmx.cn/upload/ckimg/files/202109040227061754.pdfIn PDF document text
    • https://cremeconferences.com/wp-content/plugins/super-forms/uploads/php/files/f8c10e3e84181e4eaa7de755c6546fe9/vamatigukaxima.pdfIn PDF document text
    • http://archiwum.wyryki.eu/admin/ckfinder/userfiles/files/36717240251.pdfIn PDF document text
    • http://klubalfa.org/img/userfiles/file/zolikibujisofonipok.pdfIn PDF document text
    • http://everbeenmagnet.com/js/upfiles/files/tenakuzitar.pdfIn PDF document text
    • http://epoptavky.com/is/images/FCKeditor/File/kodikajilemifujevus.pdfIn PDF document text
    • https://galaxytraining.examinationonline.com/files/68536806448.pdfIn PDF document text
    • http://ballmillfactory.com/d/files/38249678349.pdfIn PDF document text
    • http://jocoseatee.com/userfiles/files/xadapiwanul.pdfIn PDF document text
    • http://optimaglobal.net/ckupload/files/6901050970.pdfIn PDF document text
    • http://mp-hd.de/data/aktualnosci_imgs/file/6538159493.pdfIn PDF document text
    • http://dostrojar.sk/UserFiles/file/zowatewidewarozaxitog.pdfIn PDF document text
    • http://zhfangyuan.com/uploadfiles/files/popidawarobas.pdfIn PDF document text
    • https://namkhoasaigon.vn/web/images/files/zuwexuluvilixuzixomosu.pdfIn PDF document text
    • http://www.stallionreadymix.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1612f1da98871f---66751311250.pdfIn PDF document text
    • http://daydreamspin.com/userfiles/file/66924994721.pdfIn PDF document text
    • http://candybeauty.vn/upload/files/2608217187.pdfIn PDF document text
    • https://zd-zeta.com/uploads/files/202109150552006403.pdfIn PDF document text
    • http://vinhhangvien.com/upload/files/ninowafevujumedowevofal.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_off0000cf92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF92 10644 bytes
SHA-256: f00b528643495f6427ca224eabcd7e444a413ab278186289a7979ee8192b972d
font_01_sfnt_off0000e7c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7C7 17584 bytes
SHA-256: 6df570e76ddc6aaf9582fd6abaaf739b9589a9a22cdecd58a6d850f0cc1cb344
font_02_sfnt_off0001150c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1150C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1