Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b259bd8bbb60745…

MALICIOUS

PDF

97.2 KB Created: 2021-07-17 06:59:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 635c337739bfdeffe0170aafa0db02b2 SHA-1: af59bbc4c94d59e5e45eeb1fb4bc5de6a00aee46 SHA-256: 4b259bd8bbb607450c164843df3cdc186b1e754dfab0c77b17367d7cb9988e49
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious. Static analysis revealed it functions as a link farm, containing numerous URLs pointing to various websites. Several of these URLs are hosted on compromised WordPress sites, indicating a potential distribution or phishing vector. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

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://uptownherndon.com/uploads/files/11632107287.pdf In PDF document text
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1609493b877dcf---82097034917.pdfIn PDF document text
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d2c8c93b4db---taxurugemilogigej.pdfIn PDF document text
    • https://dcimx.com/files/82863772808.pdfIn PDF document text
    • https://rajaunited.com/contents//files/panupolagiludalorema.pdfIn PDF document text
    • https://www.kbstephens.com/wp-content/plugins/super-forms/uploads/php/files/56bdbeb5abc6943774dc25d8c0a3430a/14821986321.pdfIn PDF document text
    • http://banlinhkienlaptop.com/userfiles/file/vubujomow.pdfIn PDF document text
    • http://dnepropress.net/files/file/suwaxazifajegaguz.pdfIn PDF document text
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16083d1ddc16f6---revoxaj.pdfIn PDF document text
    • https://weinquartier.at/wp-content/plugins/super-forms/uploads/php/files/cc748c42661c812822fe59dc535f6eb2/pisunelez.pdfIn PDF document text
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/5mcn9hfsl03u7p8b3vk1a1rvh5/fipowaluzavigamidovulo.pdfIn PDF document text
    • https://giolog.biz/images/bulk_images/files/volukupote.pdfIn PDF document text
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607166fc02312---falajafonedabob.pdfIn PDF document text
    • https://thehideawayresortpattaya.com/userfiles/files/sejilorifegixaf.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/e51833d25bb9946646a4202aaa0fc492/lugubupemamej.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/160df698600d07---52803833471.pdfIn PDF document text
    • http://shipagents.nl/uploadfiles/file/wubalalutar.pdfIn PDF document text
    • https://pilisilovaskert.hu/ckfinder/userfiles/files/xilujulogoro.pdfIn PDF document text
    • http://simkoongschool.com/uploads/editer/files/26185021380.pdfIn PDF document text
    • http://aep-tc.com/cache/fck_files/file/82902667163.pdfIn PDF document text
    • https://onhimalayas.com/ckfinder/userfiles/files/somobopavalixavidutiwub.pdfIn PDF document text
    • https://landbondcorten.com/attachment/file/b83ceb97f29a54703920272c99226f10.pdfIn PDF document text
    • https://pensiuneavalentina.ro/app/webroot/file/kebuvuroval.pdfIn PDF document text
    • http://suncitygroup.ir/basefile/suncitygroupir/files/jupujibugarenalipiwiwov.pdfIn PDF document text
    • http://mynigaoe.com/upload/file/20210511144842.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=can+u+eat+rice+on+a+dietPDF 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_off00011bde.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BDE 10280 bytes
SHA-256: e680145e26de0c04ff413fd414320c831fdc0c70f8dddf032024b7b3d39e87eb
font_01_sfnt_off00013321.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13321 17116 bytes
SHA-256: b77800a1c38395e17e899672b04728efced37885b709ae5b9b4ca9d4e28947d7
font_02_sfnt_off00015f8f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15F8F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.