Malicious PDF — malware analysis report

Static analysis result for SHA-256 3deceed8e637cdd0…

MALICIOUS

PDF

76.3 KB Created: 2021-09-11 12:34:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 16e1558b348a276e3b911484feeec5ba SHA-1: 962b1be392b8fca274af0c541a9f4e5e1a8f3b4d SHA-256: 3deceed8e637cdd0b51e3aa3fa5cb7d6ffc3aebff1afbd5bdf1f73e1e14e56da
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external PDFs hosted on disposable domains, indicating a link farm designed to distribute malware. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were directly extracted, the PDF structure and heuristic firings point towards a malicious document designed to trick users into downloading further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9827

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://phanphoiongnhuahoasen.vn/upload/files/fokifixexipuwedivuligojul.pdf In PDF document text
    • https://ochronaskory.pl/pliki_user/File/58484584501.pdfIn PDF document text
    • http://klwas.org/userfiles/images/file/5670282074.pdfIn PDF document text
    • http://wingmanplanningdemo.com/userfiles/files/jovomibejud.pdfIn PDF document text
    • http://clarklawtexas.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/konapofirutevilawemom.pdfIn PDF document text
    • http://binhchuachay.info/Images_upload/files/xaxujawopemevagesifine.pdfIn PDF document text
    • http://broadviewlibrary.org/uploaded_bvlib/file/jevax.pdfIn PDF document text
    • http://benardoutlite.com/admin/fckeditor/fckdata/file/gofuvaxuzef.pdfIn PDF document text
    • http://hatowo.com/app/webroot/uploads/files/10480796155.pdfIn PDF document text
    • http://gaia-onlus.org/userfiles/file/37085456276.pdfIn PDF document text
    • https://thokhoavietnam.com/upload/files/6212052271.pdfIn PDF document text
    • https://brincandoeaprendendo.com/fotosempresa/files/23289537644.pdfIn PDF document text
    • https://istanbularicilikfestivali.com/upload/ckfinder/files/6844003396.pdfIn PDF document text
    • http://xn--o79av69abka850ab6c.com/upload/file/202109072002264327.pdfIn PDF document text
    • http://www.bash.cl/media/file/kakasulinilikidimuwes.pdfIn PDF document text
    • http://sakaryakasaplarodasi.org/userfiles/file/29450682915.pdfIn PDF document text
    • http://tropo-design.com/ckfinder/userfiles/files/kitapijudovirapotilalen.pdfIn PDF document text
    • http://firewaterdamagedfw.com/test/fckeditor/uploadfiles/file/milamowazugutigemu.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ea66a528e1---varimaveremoz.pdfIn PDF document text
    • http://realfootball.gr/userfiles/file/demozekugebikogi.pdfIn PDF document text
    • http://xutricolor.com/uploadfile/files/6457371932.pdfIn PDF document text
    • http://ambulatorioveterinariobubiniregini.eu/userfiles/files/gafog.pdfIn PDF document text
    • http://lso-msm.com/userfiles/file/44776036053.pdfIn PDF document text
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/161344cf850f56---1518308964.pdfIn PDF document text
    • https://agrando.cz/files/file/wefizifizane.pdfIn PDF document text
    • http://seattlebestteriyaki.com/uploads/files/46974021683.pdfIn PDF document text
    • https://klcmekatronik.com/ckfinder/userfiles/files/lenokojamevadafe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=prince+of+persia+classic+android+downloadPDF 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_off0000c767.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC767 10604 bytes
SHA-256: b130e5082018d4ce91f047e55269014266aa077acd841535b50b0cf4e1c1a951
font_01_sfnt_off0000dfc2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFC2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f7d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7D4 16648 bytes
SHA-256: 278ba44aad257d88735ba31fae90860d58c8b9c6b928490d0039ce8d3608c68f