Malicious PDF — malware analysis report

Static analysis result for SHA-256 358ad083c874c16c…

MALICIOUS

PDF

86.1 KB Created: 2021-08-13 04:47:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: ee27a94d965592a81bbc01c965b3b160 SHA-1: 20fd047ced297ef5327ee9c08aeb3a5acd403352 SHA-256: 358ad083c874c16c28036bf0d94aac8fa6956bce3c1f262e4075a43fdd78da53
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains a link farm with numerous URLs, many pointing to compromised CMS upload directories or disposable hosting, suggesting an attempt to redirect users to malicious content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, indicating it's not intended for human readability but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://accesoriosalmayor.com/images/userfiles/file/fegaxiliz.pdf In PDF document text
    • http://www.chiringuitomediterraneo.com/ckfinder/userfiles/files/putatidujo.pdfIn PDF document text
    • https://realestateconnect.us/wp-content/plugins/super-forms/uploads/php/files/lhkekvjhu7pa5snc2il2t0jk72/26189896389.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/7dd00ae030d297c9164c0b95be956208/70951236684.pdfIn PDF document text
    • http://xingyeknitting.com/userfiles/files/6651423055.pdfIn PDF document text
    • http://limoride.net/gallery/file/misapoturomaje.pdfIn PDF document text
    • http://superplasticizer.cn/d/files/77026522790.pdfIn PDF document text
    • http://amoy-art.com/Upload/file/sevoku.pdfIn PDF document text
    • http://taxfreepoint.com/file/bisuxuridumumoso.pdfIn PDF document text
    • https://promocionesnma.com/wp-content/plugins/super-forms/uploads/php/files/3009cfadf354e1b8b77a9f9b12c21ea5/nokekiviju.pdfIn PDF document text
    • http://timebank.ru/sites/default/files/photos/pagefile/70358887823.pdfIn PDF document text
    • https://rivnerun.club/images/files/madiponitewapotub.pdfIn PDF document text
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075e9c098742---zefur.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/16094b193b28c0---lotuzo.pdfIn PDF document text
    • http://sllight.ru/design/img/upload/file/3826822964.pdfIn PDF document text
    • https://baxsporthorses.nl/userfiles/file/7869051372.pdfIn PDF document text
    • https://lixtech.com.tw/ckfinder/ckfiles/files/38168858896.pdfIn PDF document text
    • http://livestreaming.group/wp-content/plugins/super-forms/uploads/php/files/absvvj36p9bd8l0049nldj3qv91r90rs/96697381923.pdfIn PDF document text
    • http://geraldinekilkelly.ie/lexote.pdfIn PDF document text
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/160d74ffd34f96---74143871958.pdfIn PDF document text
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160949a18d4e22---15895305858.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160fbc649cd8d5---fanopejudefirurese.pdfIn PDF document text
    • https://creativesilhouettes.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607b907aa2d0b---87178222467.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=moldes+de+letras+min%C3%BAsculas+para+imprimir+pdfPDF link annotation
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cb6be21055---21659292176.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_off0000e806.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE806 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010018.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10018 18156 bytes
SHA-256: 4f88474a972a9a9e9cb1b19e545f52ad6ad46781f0e6ce3f22004a13c944d1e2
font_02_sfnt_off00012e98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E98 10988 bytes
SHA-256: f2857dae1e047d334c2390030c2d5a42204c8aea4d3a0159476fae14eacae08b