Malicious PDF — malware analysis report

Static analysis result for SHA-256 d7bf16aa8b68b508…

MALICIOUS

PDF

83.4 KB Created: 2021-10-05 16:38:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: ed56d7ab50df0abd4678e8ce6fbcdc80 SHA-1: 3abf8b72b4d96035399fec5c81892411a4038924 SHA-256: d7bf16aa8b68b508bb5642fc8f4827eaf1dfd8e5bb99f063166f0aa9fc53ec76
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to multiple external URLs, some of which are hosted on compromised WordPress sites. The presence of numerous links, including those with UTM parameters, suggests a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://wastran.ru/uplcv?utm_term=chaucer+to+shakespeare+book+pdf PDF link annotation
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1614098fe1258c---duzuxakabirijiwul.pdfIn PDF document text
    • http://kammerchor-lindau.com/file/65361697232.pdfIn PDF document text
    • https://shieldtech.cz/ckfinder/userfiles/files/62196038577.pdfIn PDF document text
    • http://dasbluemchen.com/vililaj.pdfIn PDF document text
    • http://yuh-tarng.com/userfiles/file/20117167838.pdfIn PDF document text
    • http://www.oomedia.com.tw/ckfinder/userfiles/files/42181211307.pdfIn PDF document text
    • http://goldartline.ua/userfiles/file/47502460481.pdfIn PDF document text
    • http://advertisingreports.info/assets/ckfinder/core/connector/php/uploads/files/74184540701.pdfIn PDF document text
    • https://agros.net/uploads/file/semawajudoludemiximul.pdfIn PDF document text
    • https://serviceelectric.ca/userfiles/file/21181119207.pdfIn PDF document text
    • http://np-laser.com/upload_fck/file/2021-9-16/20210916185448734464.pdfIn PDF document text
    • http://utcsp2.rustyramone.com/uploads/files/5502128570.pdfIn PDF document text
    • http://zeguvietnam.com/uploads/ckfinder/files/bebezilobidozow.pdfIn PDF document text
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614cbef400671---gavasod.pdfIn PDF document text
    • http://ayurveda-shiatsu-nice.com/upload/files/vavuzubal.pdfIn PDF document text
    • http://duetsepolno.pl/userfiles/file/guzunitonurumap.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614d669b07c18---68143612578.pdfIn PDF document text
    • http://odontoflash.eu/userfiles/files/bukotuleduneratonixapasa.pdfIn PDF document text
    • http://ksiclubbiz.ksiclub.org/svnprojects/DHD/Source/images/files/dapigugepadoxotobofojis.pdfIn PDF document text
    • http://pantanalmsnews.com.br/ckfinder/userfiles/files/91967612192.pdfIn PDF document text
    • http://teamtrinity.net/trinitya/file/44261264294.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-9-12/20210912020817648153.pdfIn PDF document text
    • http://tootingtaxi.com/survey/userfiles/files/49583419434.pdfIn PDF document text
    • http://santabruna.cl/upload/file/29986210673.pdfIn PDF document text
    • http://ownlines.com/upfiles/file/punamutijerikusokow.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_off0000dcbd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCBD 19328 bytes
SHA-256: 96b68d1de65008862234b0c1d989e0ad2b8d619c0fa95ff3d50123b236847ff3
font_01_sfnt_off00010ea5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EA5 10836 bytes
SHA-256: f6256a68bdfffd2368d19970a1e977688dca84bf6f4433fcc2cd9195415e6ffa
font_02_sfnt_off000127a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127A4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1