Malicious PDF — malware analysis report

Static analysis result for SHA-256 c2e16a893eae70ff…

MALICIOUS

PDF

81.2 KB Created: 2021-10-08 14:13:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 519085ba00a4cf24082a99416613468f SHA-1: c04402b3ea3a8824c07b7616e77beaa33d1c0316 SHA-256: c2e16a893eae70ffac83687c96c19bb9bd290e715629eca082e6185f6502844c
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links to various domains, many of which are identified as a link farm on disposable hosting. The ML classifier strongly indicates maliciousness, and the presence of compromised CMS upload links further supports this. The document body is heavily obfuscated and unreadable, providing no direct content clues, but the overall structure and URL distribution suggest a lure for users to visit potentially malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 5

  • 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://synphabase.ch/upload/file/kikevatipipipux.pdf In PDF document text
    • http://xetaihyundai.net/upload/files/kuxigas.pdfIn PDF document text
    • http://royalgroup.at/tmp/mugevuritolikixixikadeluw.pdfIn PDF document text
    • https://yukkumpulgroup1.com/contents/files/medesurufun.pdfIn PDF document text
    • http://theofficefurniturestore.com/ckfinder/userfiles/files/femusikefipagilexis.pdfIn PDF document text
    • https://panoramamall.bg/ckeditor/ckfinder/userfiles/files/monasumin.pdfIn PDF document text
    • http://cn-biyoute.com/d/files/77561890396.pdfIn PDF document text
    • http://www.schule.havonix.com/ckfinder/userfiles/files/83493529292.pdfIn PDF document text
    • http://xn--9w3b270a7kf.kr/ckfinder/userfiles/files/nasadugexifawajeman.pdfIn PDF document text
    • http://dongamold.com/fckeditor/upload_files/file/36220923158.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/161490b77a4607---23580315734.pdfIn PDF document text
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/e1jjgnr00urhgafapcq2cmjgrs/51697818434.pdfIn PDF document text
    • https://stalbeckers.nl/userfiles/image/file/9626832871.pdfIn PDF document text
    • https://njsolarpower.com/wp-content/plugins/super-forms/uploads/php/files/6ea6e2b46290388e96222689d80f07e2/sexefikoranoda.pdfIn PDF document text
    • https://kawanmto.org/contents/files/bekunojirimiseweta.pdfIn PDF document text
    • http://autoscuolapezzano.it/userfiles/files/56879768672.pdfIn PDF document text
    • http://candemdientu.com/Images_upload/files/44226651834.pdfIn PDF document text
    • http://www.cddfct.com/up_files/file/zuruxoxufufiputodemevobo.pdfIn PDF document text
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16130a9057b9bc---zabavoze.pdfIn PDF document text
    • https://swapnauraan.com/ckfinder/userfiles/files/46860647103.pdfIn PDF document text
    • https://koparieshorvathbusz.hu/files/file/vejodev.pdfIn PDF document text
    • http://srihemkuntsahibfgp.org/hemkunt/userfiles/file/19815892041.pdfIn PDF document text
    • http://www.dfdtrading.sk/ckfinder/userfiles/files/fepolakimirepabovofelojo.pdfIn PDF document text
    • http://allergya.news-read.com/upload/files/xolujod.pdfIn PDF document text
    • http://foto-recepty.sk/images/fotky/pajotefubasoziga.pdfIn PDF document text
    • http://cgemfoco.com.br/ckfinder/userfiles/files/95156956555.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=practice+direct+and+indirect+object+pronouns+spanishPDF 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_off0000d44c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD44C 19248 bytes
SHA-256: b78861a782020983468699e48f36dcb9047ef0527eaa869e281ad3b70c67cbf3
font_01_sfnt_off0001053f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1053F 10936 bytes
SHA-256: 0e04935d6a3bc26355e87abb5301ac5494e1830b88fac9b6ddd464fb26de70d9
font_02_sfnt_off00011e45.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E45 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1