Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f665f64864f0bdf…

MALICIOUS

PDF

80.2 KB Created: 2021-09-16 02:56:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: c4b28e9d91c5d5a879433cb44b692498 SHA-1: d52437a7bcf02ad0731dcee1207e22ac96793302 SHA-256: 8f665f64864f0bdfe10ac0d26f94691adf5f219e2d2ca69face62ac03571807c
126 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm on disposable hosting, with numerous embedded URLs pointing to potentially malicious PDF files. The primary attack pattern involves directing users to these URLs, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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 http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/126b5bbfc4363f07f0750b98e984c36a/suwipezisikatiketudem.pdf In PDF document text
    • https://tekartltd.com/upload/files/ledaluwojop.pdfIn PDF document text
    • https://mldom.xyz/web/img/podborky/files/74634417426.pdfIn PDF document text
    • http://savalis.ru/userfiles/file/31793479495.pdfIn PDF document text
    • http://prestopc.it/upload/file/83692318392.pdfIn PDF document text
    • https://www.zochrot.org/ckfinder/userfiles/files/luvorowefanafilonuguwolax.pdfIn PDF document text
    • http://futsalcb.cz/picture/vtextu/file/kepewewitaxarobelekevam.pdfIn PDF document text
    • http://alrabbancapital.com/file/files/wirivuw.pdfIn PDF document text
    • http://siltherm.com/ckfinder/userfiles/files/nelipabifevexulewoke.pdfIn PDF document text
    • https://bayihoki99.com/contents/files/832513233.pdfIn PDF document text
    • https://bloomlight.pl/_bloom/file/34228350893.pdfIn PDF document text
    • http://expresskaliski.info/file/kesodin.pdfIn PDF document text
    • https://polenhosting.com/calisma2/files/uploads/16598955746.pdfIn PDF document text
    • https://jewfri.kr/files/image/files/29706940130.pdfIn PDF document text
    • http://otoozevran.com/resimler/files/60957556506.pdfIn PDF document text
    • http://ninda.vn/userfiles/files/15539686079.pdfIn PDF document text
    • https://2-view.org/home/view/public_html/ckfinder/userfiles/files/roduzaboganajibikabi.pdfIn PDF document text
    • http://syarmarka.ru/userfiles/files/misakekubojez.pdfIn PDF document text
    • http://gamboeng.com/assets/ckfinder/userfiles/files/42308452493.pdfIn PDF document text
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142658da3dfc---lagaxiki.pdfIn PDF document text
    • http://chinajnbt.com/images/upload/File/97405502682.pdfIn PDF document text
    • https://cjsc.se/ckfinder/userfiles/files/41220342007.pdfIn PDF document text
    • http://benetalent.com/upload/files/33773302452.pdfIn PDF document text
    • http://jiji.pgo.tw/pic/uploads/files/63385235324.pdfIn PDF document text
    • http://hanilkwanla.com/uploads/files/vipijasonim.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=android+sms+font+sizePDF 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_off0000d5f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5F6 10348 bytes
SHA-256: 545b8d49b3f44bb34ef32fa492e534bb224715faf6b5b67ed3b9c3d8c6c21c43
font_01_sfnt_off0000ed5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED5E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010570.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10570 17772 bytes
SHA-256: a409a3c78511248b68d2e9bc8d156d2e245c4beb6733c859b292d08a1fbcbd16