Malicious PDF — malware analysis report

Static analysis result for SHA-256 eac050559f4a932a…

MALICIOUS

PDF

72.1 KB Created: 2021-09-28 12:18:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f6ed9a310d2e75049a790fb7242f40ec SHA-1: 1be647a835a78a0d460b232f9854c0c1be1a8fd2 SHA-256: eac050559f4a932a97f4a2a0d1d17546de1afadf07237ff64a902afbe2f3e450
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that function as a link farm, directing users to external sites. Several heuristics indicate these links are associated with compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9915

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://cructi.ru/uplcv?utm_term=remote+desktop+server+for+android
    • http://ozdesignhouse.com/app/webroot/uploads/files/30930371855.pdf
    • http://starma.pl/files/file/89377992016.pdf
    • https://www.poolsrus.com.au/application/third_party/ckfinder/userfiles/files/53243078177.pdf
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614ac9657b653---27819757479.pdf
    • http://vocal.bpv.su/content/files/files/36025067016.pdf
    • http://mrspk.com/ckfinder/userfiles/files/61813004220.pdf
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/161472e43db7ee---69783832778.pdf
    • http://theartofdesign.nl/ckfinder/userfiles/files/18591789270.pdf
    • https://rybczewice.pl/userfiles/file/76451285674.pdf
    • http://chinazzjx.com/d/files/43248044779.pdf
    • http://tuvantindat.com/uploads/2021-09-27/images/files/71220376852.pdf
    • http://diversecityuk.com/userfiles/file/xabatuxejuteribizufexori.pdf
    • https://www.osteopathe-montpellier-sud.fr/ckfinder/userfiles/files/6334775194.pdf
    • http://cancercareresearch.com/userfiles/file/17052706672.pdf
    • http://brenna-ski.pl/userfiles/file/96732329294.pdf
    • http://stark-tools.ru/images/uploaded/56508510858.pdf
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/4haem1981lr9n5ib36rpa0lbc5/1018633923.pdf
    • http://kprmk.pl/userfiles/file/18878723898.pdf
    • https://inprovitecuador.com/ckfinder/userfiles/files/pirovidoputak.pdf
    • https://esofagopisa.it/userfiles/file/57904560164.pdf
    • http://malopolskiszlakwinny.pl/upload/File/nofibixigabusubamekati.pdf
    • https://novsport.com/content/File/61863071015.pdf
    • https://ontogepszerviz.hu/editor_up/sebogufejoremekap.pdf
    • http://zartmobilia.com/userfiles/file/20210919194747.pdf
    • http://songhandiban.com/uploadfile/file/2021091406194173499.pdf
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/6ce23815e62b47c997b39128ee6d9418/xorunanirubufajemenel.pdf
    • 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_off0000b685.bin
adff66e966f3c2835f8484d63c4a83fa2015cd48c77969c768c2e852717a866f
pdf-font-stream PDF embedded font (sfnt) at offset 0xB685 16952 bytes
font_01_sfnt_off0000e184.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE184 16792 bytes
font_02_sfnt_off0000f99b.bin
7e1ba80bf728b6644ade0aa60a6c4a13e14e40e4da22edb6e66e3ac54838d7c4
pdf-font-stream PDF embedded font (sfnt) at offset 0xF99B 10816 bytes