Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5971c0c8ef9faca…

MALICIOUS

PDF

69.1 KB Created: 2021-09-29 14:46:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 677299f6a74739d427607b7ad848edf7 SHA-1: 77a82189a159cc2e478ec7fda375c57437184140 SHA-256: b5971c0c8ef9facaa78b40c3f3aa29b9456ac41a8956f7a1b6c77740e232acd8
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The sample was detected as a malicious PDF by ClamAV and an ML classifier. It contains numerous embedded URLs, many pointing to disposable domains, characteristic of a link farm used for phishing or malware distribution. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically flags this behavior, indicating a high likelihood of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://inwebjor.ru/uplcv?utm_term=android+tv+box+wiki PDF link annotation
    • http://badischer-kunstverein.de/ckfinder/userfiles/files/nigokivabofij.pdfIn PDF document text
    • http://avandcie-automation.com/ckfinder/userfiles/files/nuvatoresererogafid.pdfIn PDF document text
    • https://alasclub.gr/neuro/ckfinder/userfiles/files/bekudirafumuzanozatel.pdfIn PDF document text
    • https://southernwashpros.com/nbloom/fckuploads/file/22569365175.pdfIn PDF document text
    • https://kidneystonetreatment.in/userfiles/files/raralawojeturuxis.pdfIn PDF document text
    • http://bigyikesmedia.com/home/xtremweb/public_html/consultinstitute/web/upload/files/janabetupukewaz.pdfIn PDF document text
    • http://umbabox.com/userfiles/file/feduvar.pdfIn PDF document text
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/161539286ba9c1---52061945630.pdfIn PDF document text
    • http://anquocrealty.com/uploads/image/files/53584689489.pdfIn PDF document text
    • https://europacreativaeuskadi.eu/files/galeria/files/nokawonevuvexafalewi.pdfIn PDF document text
    • https://roundtable106trust.org/admin/uploads/file/mogojozumogo.pdfIn PDF document text
    • https://bluetact.com/ckfinder/userfiles/files/godawaxawufupefasu.pdfIn PDF document text
    • https://seo-methodes.com/userfiles/file/makipanuxevuv.pdfIn PDF document text
    • http://cnc-soustruzeni.cz/files/file/wobopodatukup.pdfIn PDF document text
    • https://ijtm.in/userfiles/file/sebereg.pdfIn PDF document text
    • https://rimi.sk/userfiles/file/sizexofitifavixoza.pdfIn PDF document text
    • http://zuche0551.com/upload/file/8385110623.pdfIn PDF document text
    • https://relaxbotanika.cz/ckfinder/userfiles/files/82868500249.pdfIn PDF document text
    • http://ngoinvest.com/uploads/ckfinder/files/43465227695.pdfIn PDF document text
    • https://promoform.coreform.it/uploads/file/diwevag.pdfIn PDF document text
    • http://csc-027.com/userfiles/file/20210925072222_x93p9d.pdfIn PDF document text
    • http://perilatomsk.ru/ckfinder/userfiles/files/wudivifivu.pdfIn PDF document text
    • https://olekiwaszkiewicz.pl/userfiles/file/xenapane.pdfIn PDF document text
    • https://dalycity.com/wysiwygfiles/file/21563837607.pdfIn PDF document text
    • https://www.rt9.rspo.org/ckfinder/userfiles/files/64089316742.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_off0000b06c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB06C 15592 bytes
SHA-256: 256fe9dba0e87318cce383b34bc9a5841707257854c9e557aef29527aff6ea55
font_01_sfnt_off0000d809.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD809 10200 bytes
SHA-256: fbba020cb34d5fae72d381429927dd78145589af670308e35756de9d133c8820
font_02_sfnt_off0000ef09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF09 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1