Malicious PDF — malware analysis report

Static analysis result for SHA-256 e213c5781155e35e…

MALICIOUS

PDF

108.3 KB Created: 2021-09-18 14:13:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: ad9021f3d12bd2fed73cf0733a7ba876 SHA-1: b20a52db7f9ed5bb7b1317823214e6e2a79fe23e SHA-256: e213c5781155e35e527f4a293f3d1f63fd561916c0e67ee4f2ceaa78a1764bd9
156 Risk Score

Malware Insights

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

The sample was identified as malicious by a ML classifier and ClamAV, flagging it as a phishing trojan. It contains numerous embedded URLs, many pointing to compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users. The document body is heavily obfuscated and unreadable, providing no direct content clues, but the heuristic firings strongly suggest a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://f2h63c2.ip4secure.net/upload/files/14362596110.pdf In PDF document text
    • https://www.idd.no/ckfinder/userfiles/files/rilujakufoteturaguzaxipa.pdfIn PDF document text
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/qhs8ttiil59ku08ncvo94kc20d/mavobaxegu.pdfIn PDF document text
    • https://familienbilstrup.dk/ckfinder/userfiles/files/71150245347.pdfIn PDF document text
    • http://sinching.com/uploadpic/files/202109011743098148.pdfIn PDF document text
    • https://s-serviss.lv/userfiles/file/nebidinajif.pdfIn PDF document text
    • http://acril.ru/ufiles/files/kapivozalekizi.pdfIn PDF document text
    • http://apisicul.com/userfiles/files/33427103087.pdfIn PDF document text
    • http://change4best.ru/upload/file/jalevadupirexuv.pdfIn PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/edbd3d26e6fd5fc97343884dd17f660b/wofujodubona.pdfIn PDF document text
    • https://pierrelemagicien.com/userfiles/file/11162959943.pdfIn PDF document text
    • https://kcharp.com/ckfinder/userfiles/files/18549196170.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-9-8/20210908113656830775.pdfIn PDF document text
    • http://changwontour.kr/FileData/ckfinder/files/20210914_DFF1EFE5BF81EC39.pdfIn PDF document text
    • http://firewheels.pe/userfiles/file/29346698518.pdfIn PDF document text
    • http://detaycopymatbaa.com/userfiles/file/tusufitagox.pdfIn PDF document text
    • https://degardo.hollandpazsit.hu/ckfinder/userfiles/files/78879801543.pdfIn PDF document text
    • https://ka-base.no/images_students/files/75753347204.pdfIn PDF document text
    • http://africareview.in/userfiles/file/83521257156.pdfIn PDF document text
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613cc9be6116b---17512337124.pdfIn PDF document text
    • http://foto-recepty.sk/images/fotky/jerurulopomewefatosisagi.pdfIn PDF document text
    • http://bibrka-school.org.ua/ckfinder/userfiles/files/2654647654.pdfIn PDF document text
    • https://jakspravnenapsa.cz/userfiles/file/fuzezesebodexojudiga.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=goku+season+1PDF 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_off000148c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x148C6 10048 bytes
SHA-256: b42cded4eeca35337235fe107fdb9a6559d0a9f085d5e90ea6ee85875b99a729
font_01_sfnt_off00015f57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15F57 17144 bytes
SHA-256: ee4608777255bd0bff875017a639f8455a1d33ff4a48273aa5fb56c956fee505
font_02_sfnt_off00018bf6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18BF6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1