Malicious PDF — malware analysis report

Static analysis result for SHA-256 a2bd3a4e70667ca4…

MALICIOUS

PDF

73.8 KB Created: 2021-09-29 13:43:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: e07c67023c65f795471e535b1068b1f3 SHA-1: ed0c74ba97bc838c3be5c48888bf694e5f9597ec SHA-256: a2bd3a4e70667ca40236753be269c5342cc99ec45a2b846c666b4d140b493ddd
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many pointing to PDF files on disposable domains, suggesting a link farm or redirection mechanism. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a tactic to obscure the true destination. While no scripts were explicitly extracted, the nature of the embedded URLs and the overall detection suggest it's used to redirect users to malicious content, likely phishing pages or malware download sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9827

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://stihoplet.by/upload/editor/files/77927641696.pdf In PDF document text
    • http://roberlo.cz/www/files/file/51149640357.pdfIn PDF document text
    • https://hkparkkonutlari.com/image/files/kenadedebew.pdfIn PDF document text
    • http://langeline.com/ckeditor/upload/files/78748198680.pdfIn PDF document text
    • http://avvocatoandreabruschi.it/userfiles/files/75194814887.pdfIn PDF document text
    • http://kbo.pl/ckfinder/userfiles/files/24636075464.pdfIn PDF document text
    • http://nhuaduongnhapkhauaz.com/upload/files/gimefuwurabesujed.pdfIn PDF document text
    • https://kulittelor.com/contents/files/dabigapera.pdfIn PDF document text
    • https://nnkcreations.com/userfiles/file/74257082833.pdfIn PDF document text
    • http://boathousebrokerage.com/userfiles/file/93316881730.pdfIn PDF document text
    • http://autoset66.ru/admin/ckfinder/userfiles/files/51471465609.pdfIn PDF document text
    • http://baodieptailor.com/uploads/2021-09-06/images/files/81024602090.pdfIn PDF document text
    • http://tokyosushilohaus.com/uploads/files/fejajubosikoxowuso.pdfIn PDF document text
    • http://fc-junajted.com/upload/datoteke/dewer.pdfIn PDF document text
    • http://rewitex.pl/userfiles/file/lanoxaf.pdfIn PDF document text
    • http://tce.vn/imagesflashupload/file/93577295552.pdfIn PDF document text
    • https://hssanesteban.cl/files/pifarujetal.pdfIn PDF document text
    • http://www.hebrewforreadingcomprehension.com/content/wemimokinud.pdfIn PDF document text
    • http://zamaro.info/images/fcke_files/file/vevipatebiwozepisawub.pdfIn PDF document text
    • http://charugarware.com/DEVELOPMENT/charu_garware/uploaded/userfiles/file/94899832843.pdfIn PDF document text
    • https://valserve.in/web/k/main_admin/ckfinder/userfiles/files/91490886020.pdfIn PDF document text
    • https://maciejabramowicz.pl/upload/files/file/nitubufodogepe.pdfIn PDF document text
    • http://www.ap-arte.ro/fckupload/file/xokumuguxukabugit.pdfIn PDF document text
    • http://hdg-gmuend.de/userfiles/files/72456570332.pdfIn PDF document text
    • http://mmsmarin.com/imgimage/file/tepabinizo.pdfIn PDF document text
    • https://membermimpi.com/contents/files/48059662771.pdfIn PDF document text
    • https://olamare.com/img/uploaded/file/95401675341.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=animated+wallpaper+for+pc+windows+10PDF 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_off0000b957.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB957 11024 bytes
SHA-256: c02a9374d16f8092ed9a0a790aed8054bac1c17e2b7cf6f8725630858ee06c4b
font_01_sfnt_off0000d310.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD310 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000eb22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB22 18184 bytes
SHA-256: 9292f71b90bf9dcca690d17d26595361606f1c1b782bb327f90c99a43604ad0c