Malicious PDF — malware analysis report

Static analysis result for SHA-256 23fc8c9d90e6145f…

MALICIOUS

PDF

96.6 KB Created: 2021-09-07 10:37:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 1c980f09bd7cd412fc7f3cb2c4a57621 SHA-1: 3c3de4f35a87fb3a32ca396e64ebd069e66911dc SHA-256: 23fc8c9d90e6145fbe64698962df85e3598fca892810024b23e312e5aac100f2
156 Risk Score

Malware Insights

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

The PDF file contains a link farm with numerous URLs pointing to various domains, many of which are hosted on compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for SEO manipulation or to distribute further malware. The presence of multiple external URIs and link farm heuristics supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9969

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://musiconthebay.org/clients/2/26/269dd5bc96e197da989a8dccc71442af/File/66285227370.pdf In PDF document text
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/16085c31c01fd1---68881802367.pdfIn PDF document text
    • https://soechi.net/userfiles/file/xobepozibafobosivu.pdfIn PDF document text
    • http://truhlarstvisollner.cz/data/file/lebokuwiw.pdfIn PDF document text
    • https://a1-recruitment.fr/v2011/Files/fck_upload/file/73045134741.pdfIn PDF document text
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/cj2qv2k3ptgs6g9jmvq25ovne7/nepipisopofusawigaru.pdfIn PDF document text
    • https://maisonforville.be/documents/file/28677765675.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/347c54bd201882014a2382ff476b524c/12210911655.pdfIn PDF document text
    • http://daydreamspin.com/userfiles/file/86475478604.pdfIn PDF document text
    • https://www.douggoodkin.com/admin/ckfinder/userfiles/files/fifevorifijuworuwijopi.pdfIn PDF document text
    • http://ahchala.com/img/file/bosasofewuputale.pdfIn PDF document text
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e505acdb58---dedizowekesupaxasegi.pdfIn PDF document text
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/160798a8e582b4---tipolivubebopuxam.pdfIn PDF document text
    • http://konemara.hu/userfiles/file/jubibi.pdfIn PDF document text
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fbcf18974f3---2083619617.pdfIn PDF document text
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/1606c90987cee9---nevupe.pdfIn PDF document text
    • https://inlandautorepairmurrietaca.com/wp-content/plugins/super-forms/uploads/php/files/8831dfdbe9ef0792202b3a836aa5511a/1012148746.pdfIn PDF document text
    • https://xn--80aaa1anac6cg.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/a20c0d3d0795fb26f0f2afb5b57ffa9f/bubuwevogasuvexewo.pdfIn PDF document text
    • https://istanajpdua.com/contents//files/74285540594.pdfIn PDF document text
    • http://prplus4u.com/ckupload/files/safilevut.pdfIn PDF document text
    • http://webinaris.training/ckfinder/userfiles/publics/files/15725609305.pdfIn PDF document text
    • http://xn--h49al71atridzo.com/userData/board/file/mizodegulevawuxabevipur.pdfIn PDF document text
    • https://wittnebel.dk/file/nademuxaxisipigirux.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=latitude+and+longitude+practice+worksheet+answer+keyPDF 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_off000114e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114E2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012cf4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CF4 17512 bytes
SHA-256: 55b40b1338686443dc31c7a2490027eb4a202c25931d2c8c7ee673b23899d68a
font_02_sfnt_off00015a61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15A61 11140 bytes
SHA-256: c968b1f81ff268cc83fc3f7eb72edccac9cbf0e23b2de7687ff7b0af79d4ce22