Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca078079ab023591…

MALICIOUS

PDF

80.6 KB Created: 2021-09-12 21:02:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 3e3803364f34c680d4fe0476315da2d2 SHA-1: efcd212621a901d05a5d70f47fcd268505e295aa SHA-256: ca078079ab023591d804cbdba26cad05e732031f4b2e2934c16e05492e9454fc
156 Risk Score

Malware Insights

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

The sample is a PDF file flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous embedded URLs, many of which are part of link farms hosted on potentially compromised or disposable domains. The primary attack pattern appears to be directing users to malicious sites, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://pixomot.ru/uplcv?utm_term=chat+application+in+android PDF link annotation
    • https://www.funes.gob.ar/ckfinder/userfiles/files/kisomivopusezem.pdfIn PDF document text
    • http://hieuchuan.com/upload/files/sojewogenanusigutoninelaf.pdfIn PDF document text
    • http://ty-int.com/files/files/74083506164.pdfIn PDF document text
    • https://citytrafik.nu/images/file/jejiwavufelavejixeji.pdfIn PDF document text
    • http://ecme.site/2015/vat/upload/files/5503119529.pdfIn PDF document text
    • http://pttaccounting.com/userfiles/files/40049990111.pdfIn PDF document text
    • http://maradonasalud.com.ar/ckeditor/ckfinder/userfiles/files/57854349936.pdfIn PDF document text
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/1612fe958cfa90---49992414553.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/464df0c1d1e3c45161babe960172179f/rofesuja.pdfIn PDF document text
    • http://allier-genealogie.org/File:/rozub.pdfIn PDF document text
    • https://citronel.com/userfiles/files/momasaxerilifolavubopomu.pdfIn PDF document text
    • http://gazosilikatnn.ru/uploads/files/vubufikixapekapejor.pdfIn PDF document text
    • https://motoralbini.it/files/file/nilibosanotifomagejasemo.pdfIn PDF document text
    • http://krr-nfe.com/suratnfe/UserFiles/File/didetoxejiwu.pdfIn PDF document text
    • http://soleilboo.com/images/uploads/files/57121200595.pdfIn PDF document text
    • http://china-hold.com/UploadFile/file/20210901180712412.pdfIn PDF document text
    • http://3dtechgroup.com/uploads/image/files/51501110860.pdfIn PDF document text
    • https://lochoanggia.com/upload/files/jimosos.pdfIn PDF document text
    • http://eqletstalk.com/uploads/files/202109040648035248.pdfIn PDF document text
    • http://gomientrung.vn/uploads/image/files/tisesawi.pdfIn PDF document text
    • http://halanmilk.com/upload/files/tavapodadegebisijawo.pdfIn PDF document text
    • http://a-pro-peau.fr/userfiles/file/tapisopaju.pdfIn PDF document text
    • https://chmelo.hu/sites/default/files/file/mutovadojijebu.pdfIn PDF document text
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133258e4fdac---jajikobabuj.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_off0000d9c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9C9 16844 bytes
SHA-256: f245a38eb0954400d479961b35607d0f6ad7336c85c38ee077c669e4a6887af6
font_01_sfnt_off00010575.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10575 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011d8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D8C 10344 bytes
SHA-256: b757415a3bdc584ea2656c261525e707a490d20e53d3099f41eeb8ab9fff94aa