Malicious PDF — malware analysis report

Static analysis result for SHA-256 1e8943b44a21af78…

MALICIOUS

PDF

133.0 KB Created: 2021-09-19 11:51:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f9853ac03072e548bd3d0ef55b319e3f SHA-1: cf77b93c88fae2314fd9c72d7740c604d435b105 SHA-256: 1e8943b44a21af78c431d0e46c4f11e4cc81393d9a002ef2e2d76ea09308ff24
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous links pointing to compromised websites and disposable hosting, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are indicative of a malicious document, potentially leveraging embedded JavaScript for redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9945

Heuristics 7

  • 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.
  • 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 http://mzch.pl/userfiles/file/54096998008.pdf
    • http://wrtour.com/FileData/ckfinder/files/20210917_1C033703B97D6574.pdf
    • https://purpleleafestatebuyers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144ec916569e---15414003728.pdf
    • https://liur-krd.ru/userfiles/file/96986577106.pdf
    • https://festivaldelmaridaje.com/sgi_userfiles/userfiles/files/57380476354.pdf
    • https://big-affaires.com/img/pics/files/98164313411.pdf
    • http://achilleferolla.it/userfiles/files/mavasedujejitena.pdf
    • https://sierrainstruments.cn/fckeditor/editor/filemanager/connectors/php/fckeditor/upload/202109/file/nonadovamonemukadowibu.pdf
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/161388110c6861---fomefixipajiwujegabugive.pdf
    • https://www.domaine-de-la-ferme.fr/ckfinder/userfiles/files/netoligolimeligi.pdf
    • http://grandwatergatehotel.com/upfile_hotel/files/pogosuf.pdf
    • https://mallarpurnaisuva.org/go/file/fonuwelitewakevizasosonoz.pdf
    • https://hylyt.co/wp-content/plugins/super-forms/uploads/php/files/a2ef6b2cfc2659977acac80ae048e0ef/83989841770.pdf
    • http://youngshiny.com/userfiles/file/1631833330.pdf
    • http://chinalabware.es/d/files/83278484858.pdf
    • http://freeorden.com/media/file/jigafurilu.pdf
    • https://mimpishio1.com/contents/files/pusudasogilirurazaguj.pdf
    • https://mldom.xyz/web/img/podborky/files/81571873862.pdf
    • http://ambulatorioveterinarioscapindandrea.it/userfiles/files/pimewo.pdf
    • https://cissud.com/uploads/ck_editor/files/8492688752.pdf
    • http://verzorgingsindex.nl/images/uploads/zarazemogumodokikiki.pdf
    • https://afanasyev-design.ru/wp-content/plugins/super-forms/uploads/php/files/a160ebdc8ab17de7ac0305da839a7cd2/zejixajejab.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=custom+rom+finder
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001a2e6.bin
76fa5ca575f871a5fd9c54d3dd2512d6877f86873b8494deca8faba977a210b8
pdf-font-stream PDF embedded font (sfnt) at offset 0x1A2E6 19680 bytes
font_01_sfnt_off0001d692.bin
d142d6f9d46d7dcc658829b48154f3a1d6ad4319148cc3af8ae4c634f94b1cad
pdf-font-stream PDF embedded font (sfnt) at offset 0x1D692 10440 bytes
font_02_sfnt_off0001ee42.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1EE42 16792 bytes