Malicious PDF — malware analysis report

Static analysis result for SHA-256 89ef1398c77e1641…

MALICIOUS

PDF

75.0 KB Created: 2021-09-18 19:08:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e4e0e6e8a09cf9799bda86adeaca8ca2 SHA-1: 6d971a1d2cbef762889e522d2f71cf4b16689667 SHA-256: 89ef1398c77e1641b7dff91871a62a0cb0c5e38bcb8062c84eeb2b68cf2301cf
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to various domains, many of which are flagged as link farms on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. While no scripts were explicitly extracted, the PDF structure and embedded URIs suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://queure.ru/uplcv?utm_term=extract+source+code+from+apk PDF link annotation
    • https://braindevelopmentmaps.org/userfiles/files/34191807454.pdfIn PDF document text
    • https://www.tahitotfalu.hu/ckfinder/userfiles/files/nipogagamexosipumuvixez.pdfIn PDF document text
    • http://eska-lift.ru/userfiles/file/fadodokudini.pdfIn PDF document text
    • http://theffirm.com/userfiles/file/kuxaloji.pdfIn PDF document text
    • https://winpoasia.com/ckfinder/userfiles/files/risoxag.pdfIn PDF document text
    • https://phatgiaolongan.com/upload/ckupload/files/5535352905.pdfIn PDF document text
    • https://0286869143.com/editor_images/files/pixubezitemuminufudibak.pdfIn PDF document text
    • https://ylwlgwadmin.ylwl.cn/upload/files/15577987800.pdfIn PDF document text
    • http://www.miyadenthai.com/image/upload/File/49308956839.pdfIn PDF document text
    • http://hausdergesundheit.net/userfiles/files/pedepomin.pdfIn PDF document text
    • http://doo-san.com/userfiles/file/20210901182946.pdfIn PDF document text
    • http://furnitura-syndicat.ru/ckeditor/ckfinder/core/connector/php/uploads/files/86287685514.pdfIn PDF document text
    • http://sgpeo.pl/users/file/pagezomivewe.pdfIn PDF document text
    • http://narnivet.com/userfiles/files/18324369643.pdfIn PDF document text
    • http://imobilestore.de/userfiles/file/xuvinopotemudixozonez.pdfIn PDF document text
    • http://alocainghien.com/uploads/userfiles/file/dogajositasujukuzosiri.pdfIn PDF document text
    • http://plenaseguroseprevidencia.com/fotosempresa/files/35441045333.pdfIn PDF document text
    • http://rigassprotes.lv/uploadz/file/rapofowabuzi.pdfIn PDF document text
    • http://hwayoung.kr/upfile/files/gemebudojadera.pdfIn PDF document text
    • http://mitcostruttori.it/userfiles/files/tasive.pdfIn PDF document text
    • http://www.gitialiganjlko.org/ckfinder/userfiles/files/dexoretajebexulunopaboge.pdfIn PDF document text
    • https://mchs.kz/userfiles/File/piwajimurukupeva.pdfIn PDF document text
    • http://zjgyuanhong.com/v15/Upload/file/20219161834452259.pdfIn PDF document text
    • https://dolupin.com/calisma2/files/uploads/42809008573.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_off0000c02d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC02D 17348 bytes
SHA-256: a3fdba38535f4737bfa5afb39131b064323a814fab7c05a476d14c4673413853
font_01_sfnt_off0000ed53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED53 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001056a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1056A 10816 bytes
SHA-256: f6f5e2883974115b116ce08f6aee08699294fb4c41909c81cefdcca52d1964b2