Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b90ef935c350900…

MALICIOUS

PDF

85.5 KB Created: 2021-09-06 06:37:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 1d2d6ef9b95036abdc5519899d412599 SHA-1: 51873231aec8d8eff2c69f3f2d6e1f54def83653 SHA-256: 1b90ef935c350900b87a20f07cf48a36fc301dd41d49712fcc008ede50b50857
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or malware distribution attempt. It functions as a link farm, with numerous URLs pointing to potentially compromised websites or disposable hosting, designed to lure users to malicious content. The presence of external URIs and link farm heuristics strongly suggests an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://salkim.com/userfiles/file/91698051670.pdf In PDF document text
    • http://globalcenterhotels.com/bot/ckfinder/uf/files/tudidizutegaki.pdfIn PDF document text
    • https://sellerflows.com/wp-content/plugins/super-forms/uploads/php/files/bcc34dbf77c82ca2bd6411190457c9f8/56765893077.pdfIn PDF document text
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/9oik5tpilo6pfrrrdmedb52ifp/54370911732.pdfIn PDF document text
    • http://polins.org/public/userfiles/file/gamukedi.pdfIn PDF document text
    • http://skogsformedling.se/bilder_umeny/File/34604020024.pdfIn PDF document text
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/87fd624e869c531024f754a622047387/98588672141.pdfIn PDF document text
    • https://sardavetri.it/userfiles/file/kinevakuwitusa.pdfIn PDF document text
    • https://readandenjoy.ae/userfiles/files/zulusudasurebojujefuji.pdfIn PDF document text
    • http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/io99fts1tvednagqa5r26g4u2h/82093452641.pdfIn PDF document text
    • http://xn--80aaeiengkwpz6p.xn--p1ai/pub/file/51856800976.pdfIn PDF document text
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/shdnvig7p9u1p6b0qo5nk3j9a0/sepofanubazem.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a4595827598---morepufonegi.pdfIn PDF document text
    • http://rolmech-strzelno.pl/Upload/file/11201230223.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1611a9578814a5---45655219970.pdfIn PDF document text
    • http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160735453ad65d---pevabelikuk.pdfIn PDF document text
    • http://pokorny-podlahy.cz/UserFiles/File/lajemudabaxovimorudakagak.pdfIn PDF document text
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abb0738fa93---67687955800.pdfIn PDF document text
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160f98cd2235df---zakoragujovopebegu.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/hlu4ule1jabi325o08fph2ar7t/dusojalezifez.pdfIn PDF document text
    • http://maketmaster.ru/admin/ckfinder/userfiles/files/28855730514.pdfIn PDF document text
    • https://sitpchemcieszyn.pl/_sitpchem/file/33397369958.pdfIn PDF document text
    • https://rumputhijau.com/contents/files/mudanosenezezelejiko.pdfIn PDF document text
    • http://agiusfuneraldirectors.com/files/file/xiwezaderomizuxobaforekot.pdfIn PDF document text
    • http://all-pass.com/folder/editor/file/46775807039.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=check+sheet+example+pdfPDF 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_off0000e9f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9F6 17604 bytes
SHA-256: 5122e2b9421129a9c38b0c76b1fa96169f7d59e8928399fca5ab71d4560f9583
font_01_sfnt_off00011757.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11757 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012f6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F6E 10696 bytes
SHA-256: 14e59104a99d8d6ecedaad5d65df607963ba94db9d6ca3f41acda6fae88a06e3