Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7b6817426919502…

MALICIOUS

PDF

71.5 KB Created: 2021-09-05 10:27:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 89c641197cfb4d7ce68cc370d4f84849 SHA-1: 927a8382e496315b7d1a05c1eeb934bb5bf4a9b9 SHA-256: b7b681742691950207675e3c2cbdee0abf0babc1fa6a74d00b6cca5ec8720802
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories and disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users into downloading further malware or visiting phishing sites. The primary attack pattern observed is the use of a link farm within the document to redirect users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/160de880852f45---dinakugiduxipexevaja.pdf In PDF document text
    • http://computergramm.com/userfiles/file/24360736682.pdfIn PDF document text
    • http://80tner.netsociality.com/upload/files/7448832716.pdfIn PDF document text
    • https://alteanetworks.fr/img/file/66808840574.pdfIn PDF document text
    • http://ahkjt.com/upfile/file/79519382779.pdfIn PDF document text
    • https://akvaguru.hu/user/file/4761816146.pdfIn PDF document text
    • http://gianphoiduyloimodel.com/Images_upload/files/bobetakemolonusezesi.pdfIn PDF document text
    • http://longarmquiltacademy.net/fckeditor/userfiles/file/meranejixodatiw.pdfIn PDF document text
    • https://psychologgia.pl/Upload/file/45654406846.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607262d5a4839---74534327356.pdfIn PDF document text
    • https://www.truegridpaver.com/wp-content/plugins/super-forms/uploads/php/files/ca3f5b0dc81d8cdfa8010b75c01cd939/mumumifibos.pdfIn PDF document text
    • https://serka.com/serka/upload/files/rawavisezamumirijekiwum.pdfIn PDF document text
    • http://eatoceanic.iorderfoods.com/uploads/files/6295190163.pdfIn PDF document text
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/e4b12663cd9c12cd9f8ff5d1eeb89b34/mufisadusubodirutigod.pdfIn PDF document text
    • http://goodtraefarm.com/ckupload/files/turet.pdfIn PDF document text
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae2a03e0a08---55761074964.pdfIn PDF document text
    • https://alemarferries.alemarsnp.gr/ckfinder/userfiles/files/mukekugexunujazur.pdfIn PDF document text
    • http://carnavaldemarbella.com/Senegal_5/Content/files/userfiles/file/bonuxefexoratojivupumivo.pdfIn PDF document text
    • http://asremajazi.com/uploads/files/75932896054.pdfIn PDF document text
    • http://dj-venci.com/uploads/pages/files/ramujivedafesero.pdfIn PDF document text
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081ac72b88a9---buzusamimuxo.pdfIn PDF document text
    • http://serting.eu/userfiles/files/totepev.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=the+four+loves+cs+lewis+pdf+free+downloadPDF 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_off0000b628.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB628 10832 bytes
SHA-256: eaeb59eaa2d5987a0f232b442cd66c4f59c2722898172b4d80234feb346c6381
font_01_sfnt_off0000cf20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF20 16000 bytes
SHA-256: 77f508326b3ee12de28b5bdca92e446160641ae6bd2de4b8a2ab26f1740ad453
font_02_sfnt_off0000f810.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF810 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1