Malicious PDF — malware analysis report

Static analysis result for SHA-256 70ed7905f39269d6…

MALICIOUS

PDF

79.9 KB Created: 2021-09-11 01:04:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 65db9108846e7f84d7259aa39cc8a90d SHA-1: f90b22a7bb7bcffbb81c689688e9081368c3656b SHA-256: 70ed7905f39269d6b7d8df54f4e92142a06bd7904ac04739319cb88b819e5f3c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF identified as malicious by ML classifiers and ClamAV. It contains numerous embedded URLs, many pointing to other PDF files hosted on various domains, suggesting a link farm or content distribution network. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a pattern of using disposable hosting for a large number of links, often associated with SEO abuse or malware distribution. While no scripts were explicitly extracted, the nature of the embedded links and the heuristics suggest an attempt to redirect users to potentially malicious content or manipulate search engine results.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

Heuristics 5

  • 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.
  • 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://mvpbuilding.com/userfiles/file/12996741304.pdf In PDF document text
    • http://codemessaging.net/ckfinder/userfiles/files/18881716054.pdfIn PDF document text
    • https://studiovizia.com/webroot/img/content/files/39728152341.pdfIn PDF document text
    • http://longvu.vn/Images_upload/files/xodaboposotimafanokukop.pdfIn PDF document text
    • http://finemetal-cn.com/upload/files/lepok.pdfIn PDF document text
    • http://hasdeu.md/data/userfiles/files/runiruregomofizam.pdfIn PDF document text
    • http://kingbikeonline.com/images/upload/File/9875192848.pdfIn PDF document text
    • http://webinaris.net/ckfinder/userfiles/publics/files/ziniwaxivanuxowajizekulow.pdfIn PDF document text
    • http://oishisushigd.com/uploads/files/gozitikajolozagani.pdfIn PDF document text
    • http://emeat.ru/var/files/wonarajeg.pdfIn PDF document text
    • https://10s317.com/uploads/files/202109011410495178.pdfIn PDF document text
    • http://forma8.kz/ckfinder/userfiles/files/78831910919.pdfIn PDF document text
    • https://tvsporedi.si/vsebina/13386567769.pdfIn PDF document text
    • http://nemdanangpho.com/uploads/2021-09-03/images/files/fexalagesupo.pdfIn PDF document text
    • https://eko-briketes.lv/userfiles/files/jumowarudedirifufe.pdfIn PDF document text
    • http://invest.pl/userfiles/file/3906913367.pdfIn PDF document text
    • http://darstin.com/userfiles/files/20749794816.pdfIn PDF document text
    • http://www.smartusb.info/images/library/File/genelise.pdfIn PDF document text
    • http://www.nachtruhe.info/up/files/masidalekisogewipujuwoda.pdfIn PDF document text
    • http://litho-and-co.fr/ckeditor/upload/files/52489798199.pdfIn PDF document text
    • http://geoscan.it/userfiles/files/16066576255.pdfIn PDF document text
    • https://costumeworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ac2f0f379a---96900283124.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=hide+my+root+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_off0000d31b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD31B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eb2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB2D 18260 bytes
SHA-256: 9e60e2bab6132209db7221086b25f86aa2f49246ddfe80ab385a0b06eb1fd8b7
font_02_sfnt_off00011b2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B2A 10432 bytes
SHA-256: 20c7bee7e65963417fe9c597e91c44c724a3a401438465bb44bc8f39dbd6d126