Malicious PDF — malware analysis report

Static analysis result for SHA-256 d7eaf00f67d424c3…

MALICIOUS

PDF

76.1 KB Created: 2021-10-05 14:21:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 9fe7be693b473a8070d2936a7615f7b4 SHA-1: 7a45c666cc42bf31ddeccb7065d13087d6c3b567 SHA-256: d7eaf00f67d424c33cd81599321ea52ef1545f501d7803e4c56f952c3c62fcea
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URIs, many of which are hosted on disposable domains and utilize UTM parameters, suggesting a link farm or phishing lure. The PDF structure itself, combined with the heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM', points towards a campaign distributing malicious links rather than a direct exploit.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://philabc.ru/uplcv?utm_term=world+record+weakfish PDF link annotation
    • https://bk.knu.ac.kr/ckfinder/userfiles/files/sudiwakonixojupo.pdfIn PDF document text
    • http://satisfytech.com/ck/upload/files/70838995566.pdfIn PDF document text
    • https://amityhr.com/userfiles/file/letazaresibekulewopafuta.pdfIn PDF document text
    • https://ingatlanfelugyelet.hu/uploads/file/mazajewarovivasaw.pdfIn PDF document text
    • http://alessandrobelleseveterinario.eu/userfiles/files/zanonup.pdfIn PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/ac5a75076ca35bda8628e702d2c05b6e/jujoxunowotoja.pdfIn PDF document text
    • https://aartipalette.com/userfiles/file/ridegulirogafalopegesaf.pdfIn PDF document text
    • https://mobile-translator.eu/app/webroot/media/files/parebagadasumolapokudov.pdfIn PDF document text
    • https://ytdrive.com/CKEdit/upload/files/mogipidemepo.pdfIn PDF document text
    • https://www.adoz.cz/ckfinder/userfiles/files/14233098327.pdfIn PDF document text
    • https://testgit.begurholidays.com/uploads/userfiles/files/27676111113.pdfIn PDF document text
    • https://thefencedocumentary.com/adminfiles/file/53322546414.pdfIn PDF document text
    • http://nfc-lampang.com/user_img/files/moloku.pdfIn PDF document text
    • http://hoanhaochemical.com/uploads/files/460938457.pdfIn PDF document text
    • https://deltagroup.bg/uploads/file/3316128294.pdfIn PDF document text
    • https://sanaspinler.com/calisma2/files/uploads/vetegujepigabeg.pdfIn PDF document text
    • http://galantemontagnana.it/ckfinder/userfiles/files/jinaj.pdfIn PDF document text
    • http://wami.cc/data/files/62438507906.pdfIn PDF document text
    • https://ksmt.edu.np/assets/ckfinder/userfiles/files/18212919836.pdfIn PDF document text
    • http://abwingssuffolk2.com/uploads/files/76092587368.pdfIn PDF document text
    • http://keystoparadise.com/userfiles/files/99740869475.pdfIn PDF document text
    • https://fullgame.hu/uploads/files/wusuxelosipusukokimafawi.pdfIn PDF document text
    • http://image.dlib.vn/libedu/news/bvu/20210920/file/40786895858.pdfIn PDF document text
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/161483536b43d0---64924671145.pdfIn PDF document text
    • http://hoteldazegliotorino.com/userfiles/files/kusapetitivuguzil.pdfIn PDF document text
    • 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_off0000c483.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC483 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dc95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC95 17632 bytes
SHA-256: 540b8916ef6a553e3cf183340d9a524c8450fcbde5ed77e50c5b33047ea01ab9
font_02_sfnt_off00010a40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A40 10544 bytes
SHA-256: 9ea47a9e25bfc970892a45141fd71e32df3d85a9492cc9ce6c23d82c99c07bea