Malicious PDF — malware analysis report

Static analysis result for SHA-256 2c8a761d36538ec5…

MALICIOUS

PDF

86.0 KB Created: 2021-09-15 09:47:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: fd359a536552de328e5f23f846a0cd0f SHA-1: b3466686e8ea6ce5ba39ce8ff59d2a70b39cace3 SHA-256: 2c8a761d36538ec5201b813a9693d6f771d02faaca94f95b6b4fd2482e9ace2a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or malware distribution intent. It functions as a link farm, containing numerous URLs that point to other PDF files hosted on compromised websites or disposable domains. The presence of external URIs and link farm heuristics suggests an attempt to lure users to malicious content, potentially for credential harvesting or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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 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://40parables.com/wp-content/plugins/super-forms/uploads/php/files/0ee92f3c07e889463076f8666c7da1ad/5120069109.pdf In PDF document text
    • http://fourfoods.com/images/files/53512473112.pdfIn PDF document text
    • http://morpheus-architects.com/file_media/file_image/file/nurubonitasadapamaja.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614125e4c19a3.pdfIn PDF document text
    • http://uptownherndon.com/uploads/files/fanutudel.pdfIn PDF document text
    • http://gnatowski.pl/attachments/file/40758539981.pdfIn PDF document text
    • http://www.lbf-cosmetics.com/website/wp-content/plugins/formcraft/file-upload/server/content/files/16139145b565bf---zepopufigititijexot.pdfIn PDF document text
    • http://griesvoegwerken.nl/UserFiles/file/novore.pdfIn PDF document text
    • https://noursportevents.com/wheelmarine/userfiles/file/mavumijitafafudidibasafam.pdfIn PDF document text
    • http://futimisdev.com/userfiles/file/1368359088.pdfIn PDF document text
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613db482e455b---41462099881.pdfIn PDF document text
    • http://ombs.ru/uploads/files/78478539300.pdfIn PDF document text
    • http://amunt.madteam.net/ckfinder/userfiles/files/liwumokiledirakone.pdfIn PDF document text
    • http://veterinariomauracotti.it/userfiles/files/12088141399.pdfIn PDF document text
    • http://effektfilm.de/files/file/88586033665.pdfIn PDF document text
    • http://andreuma.madteam.net/ckfinder/userfiles/files/gavisigarisilagidire.pdfIn PDF document text
    • https://inchiriereelicoptere.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161419445de205---dadupanixunivi.pdfIn PDF document text
    • https://crbz.ru/userfiles/file/37893039963.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/72895570165.pdfIn PDF document text
    • https://llibreriaha.com/img/events/file/guvizis.pdfIn PDF document text
    • http://jpsacademy.com/slbdavbatala/userfiles/file/femaroroduserumifuwediku.pdfIn PDF document text
    • http://studiotecnicofrisoli.com/userfiles/files/63088888059.pdfIn PDF document text
    • http://canadianartistic.com/userfiles/file/xopamanawojuzokajolob.pdfIn PDF document text
    • http://mawratanews.com/armedia/uploads/files/duruvegoduzefejigezawu.pdfIn PDF document text
    • http://makrostal.pl/user_images/file/wogalotuvawuwowevisevefu.pdfIn PDF document text
    • http://iamsoldierfit.com/wp-content/plugins/formcraft/file-upload/server/content/files/161351b9069052---43095684797.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=best+macro+app+androidPDF 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://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_off0000ed42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED42 10680 bytes
SHA-256: 8c4a39baef3b219610a97031d137e954d9e905e8141cacc4d34a7491fc43270c
font_01_sfnt_off000105bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105BD 18592 bytes
SHA-256: 0fe5bdb82d99311c9f9c8d3a7b22baeba951b5a76cf6b307d8b2c6ea5ed0a791
font_02_sfnt_off00013580.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13580 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1