Malicious PDF — malware analysis report

Static analysis result for SHA-256 4108555ab339bd70…

MALICIOUS

PDF

106.8 KB Created: 2021-08-06 00:51:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 573b5de0ecdc7753c1b0df3df9befd25 SHA-1: 4448e3cf0252cdff7e40cf723262d98db22bcc2b SHA-256: 4108555ab339bd70bc4fb7413951b48505dbaa5b748dccf1a7fcbbf4f1924ba8
156 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ClamAV and an ML classifier. It contains a link farm pointing to multiple compromised WordPress upload directories and disposable hosting sites, suggesting an attempt to distribute malicious content or manipulate search engine results. The presence of numerous external URIs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicate a focus on directing users to external, potentially harmful, web resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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://airconbank.com/upload/fckeditor/file/rixukatezujig.pdf In PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160a8d6cc3a2ab---rinutejo.pdfIn PDF document text
    • https://binhruamuinanobac.com/wp-content/plugins/super-forms/uploads/php/files/pth04fdjt731j7nuejm5ds3g1m/wodajovazevexobogalirog.pdfIn PDF document text
    • https://bk.knu.ac.kr/ckfinder/userfiles/files/71052736796.pdfIn PDF document text
    • http://elijasprojekts.lv/files/file/5001339487.pdfIn PDF document text
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/a4b0eb26b18376719b9372d22f3953f9/pupubit.pdfIn PDF document text
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/c1iecaoluldjdlevfd4rdgvjc5/31269550914.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608002209ed8a---4450092370.pdfIn PDF document text
    • https://www.tonygssoulfood.com/wp-content/plugins/super-forms/uploads/php/files/457ab0c37f0787082c30121c2f39642c/luzokuzujigigifopim.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/s4640e34nhh75mvsmdnqg4efao/7241532584.pdfIn PDF document text
    • http://domeinbeverdonk.be/assets/files/file/kininajewita.pdfIn PDF document text
    • http://www.ambredore.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c3d82de9b3---buxorowanupironekug.pdfIn PDF document text
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c3b06196db---19599642178.pdfIn PDF document text
    • http://tsg-edinstvo.ru/userfiles/file/jopeloliwusujimilute.pdfIn PDF document text
    • http://goldmustang.com/files/files/zupalixisow.pdfIn PDF document text
    • http://poltinik.ru/userfiles/file/83053342333.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc47f677afa---57200050842.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b131f86e474---boximikupavexororo.pdfIn PDF document text
    • http://trunghungplastic.com/luutru/files/69577746224.pdfIn PDF document text
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/6923310b8a6a4c62fc76e71c4a4ddf37/86116001839.pdfIn PDF document text
    • https://clinic4lab.com/upload/ckfinder_temp/files/20210626143629.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/55f9235b294c2ad94081efd82540b5fc/25611885724.pdfIn PDF document text
    • http://abwgulfport.com/uploads/files/zapepifesizufi.pdfIn PDF document text
    • http://www.schule.havonix.com/ckfinder/userfiles/files/47108087037.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=hypothesis+testing+exam+questions+and+answers+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_off00013a3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A3C 11440 bytes
SHA-256: b2b52abf225cc8b8a796c415e6d248a5d60516204b7fe234f4c2fcbf2a3dab84
font_01_sfnt_off0001549b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1549B 17944 bytes
SHA-256: 9d46adcd31b21cd3a31aa72683e67f9a7b3b3e43eb9b5754f2e30b9850f04534
font_02_sfnt_off000183d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x183D0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1