Malicious PDF — malware analysis report

Static analysis result for SHA-256 71af8d11f840363e…

MALICIOUS

PDF

88.1 KB Created: 2021-09-05 07:15:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 85f63c458ceeeb049b8e08d29bbd85fc SHA-1: 11c7bf7983bee8ddda905f1bc9cb5bd56193ac8b SHA-256: 71af8d11f840363e6aad362f20dd1a401f4749759afe40cfb44314a6e1f4e467
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external URIs and links to potentially compromised WordPress upload storage and disposable hosting, suggesting it functions as a lure to external malicious content. The PDF structure and embedded links point towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 https://infrive.ru/uplcv?utm_term=manual+de+identifica%C3%A7%C3%A3o+e+controle+de+plantas+daninhas+fmc PDF link annotation
    • http://btc-ltd.com/upload/file/tatazopevodoki.pdfIn PDF document text
    • https://consultingexpert.eu/fckeditor/userfiles/file/zulevuxasefimudefake.pdfIn PDF document text
    • http://nusratali.com/userfiles/files/fosig.pdfIn PDF document text
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607859f857568---wukamawibid.pdfIn PDF document text
    • https://peiitw.com/Upload/ckeditor/files/jivizopogotew.pdfIn PDF document text
    • https://skyzoan.com/cake/beta/userfiles/file/31061191241.pdfIn PDF document text
    • http://tupnate.com/ckfinder/userfiles/files/64263846255.pdfIn PDF document text
    • https://transpack-krumbach.de/_upload_bilder/_filemanager/file/64659159910.pdfIn PDF document text
    • https://groupunsur1.com/contents/files/dipovupivawezuv.pdfIn PDF document text
    • https://barcelonamedicalcenter.com/files/galeria/files/rituwozofija.pdfIn PDF document text
    • http://dodici12.ru/wp-content/plugins/super-forms/uploads/php/files/6u90ssb7kq0792j42rppvaonj2/xikufixejukuluwapa.pdfIn PDF document text
    • http://euro520.net/userfiles/file/1628170981493088517.pdfIn PDF document text
    • http://cristal-in.fr/userfiles/file/moxetagovufomatilo.pdfIn PDF document text
    • https://betalinktech.com/blmedia/file/52256698069.pdfIn PDF document text
    • https://mtydizayn.com/userfiles/file/62327187429.pdfIn PDF document text
    • http://fitviewer.de/files/file/gugafudimik.pdfIn PDF document text
    • https://kaptenhoki.net/contents//files/74545658436.pdfIn PDF document text
    • http://www.sec-ollivier-associes.fr/www/upload/file/karoxin.pdfIn PDF document text
    • https://chpcentre.com/files/file/34089546530.pdfIn PDF document text
    • https://anmoul.com/userfiles/file/lafopapatetule.pdfIn PDF document text
    • https://shotclock.ca/wp-content/plugins/super-forms/uploads/php/files/6cb21055df88ec822964e6887a797b95/tuforamif.pdfIn PDF document text
    • http://ackerviewguesthouse.com/userfiles/file/80307807616.pdfIn PDF document text
    • http://enidental.com/userfiles/file/20210814111426.pdfIn PDF document text
    • http://regimhotelierbucuresti.com/images/userfiles/dosazuzuvogurufepewadij.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/f826ae74d08e3b54be3b699f1db7f30c/pazularegarinav.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_off0000e894.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE894 21100 bytes
SHA-256: b1141ad4d95932c9cf7952860a48346b9ef7673420c01e2248e75fd3ff524cca
font_01_sfnt_off00011d60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D60 11440 bytes
SHA-256: ab9315b28485779017622cb5a4fe5dc8cbe0c2997540ed0e94b08f9cecddbb71
font_02_sfnt_off0001376c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1376C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1