Malicious PDF — malware analysis report

Static analysis result for SHA-256 626681a2eb89f7b5…

MALICIOUS

PDF

110.6 KB Created: 2021-09-01 10:15:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: c94e69e2805b24cedb0ebbb888061f2f SHA-1: 117f7c7c1b5e143d4de6795277c317f25489335f SHA-256: 626681a2eb89f7b5b74685baf451a0cfbcdf68ba354b65f88ca0e2973b1b58fc
96 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to other PDF files, many hosted on compromised CMS upload directories. This structure is indicative of a phishing or malware distribution campaign, where the initial PDF serves as a lure to access further malicious content. The ML classifier strongly supports the malicious nature of this document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

Heuristics 5

  • 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://ajtoablakcentrum.com/_user/file/weduvofe.pdf In PDF document text
    • http://mariondhuique-mayer.com/data/file/gavopivi.pdfIn PDF document text
    • http://webbuilders.com/files/file/nuxegavepirudejiw.pdfIn PDF document text
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b86dd1a1b1d---saxitogakipotamilabewatow.pdfIn PDF document text
    • http://viajesalaos.com/webroot/img/files/sosiji.pdfIn PDF document text
    • http://mlmrockstars.com/ckfinder/userfiles/files/47569429458.pdfIn PDF document text
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082a6756b2a9---dixazeteluvorof.pdfIn PDF document text
    • http://lafenicealcamo.it/userfiles/files/61616885592.pdfIn PDF document text
    • http://pol2-simf.ru/userfiles/file/44922357185.pdfIn PDF document text
    • https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/f2fc803703309dc2d7a441a2aa909678/84788433719.pdfIn PDF document text
    • https://777mto.com/contents//files/runivugenakugekugabizivad.pdfIn PDF document text
    • https://stakeoutllc.com/wp-content/plugins/super-forms/uploads/php/files/7762b82510bef2aed2784b68fcccf540/53003869671.pdfIn PDF document text
    • https://webmenuplus.com/images/file/36461755131.pdfIn PDF document text
    • https://ymvii.com/admin/upload/files/33269388518.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c7a6fc92826---vakubunij.pdfIn PDF document text
    • http://deckdreams.ca/clients/3/34/34055ef41782f8f15ebf372c1e39ecad/File/40514120586.pdfIn PDF document text
    • http://apple888.vn/luutru/files/fetenamakuse.pdfIn PDF document text
    • https://www.synergyheart2heart.team/wp-content/plugins/super-forms/uploads/php/files/fppsrbackkk1bgrfi2nbvb5qqb/8371864691.pdfIn PDF document text
    • https://clifestyle.net/uploades/userfiles/file/mukoketetozobevo.pdfIn PDF document text
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/ab5d7471013b0cc5424c724c29c55580/7926037840.pdfIn PDF document text
    • http://hig-hegmann.de/userfiles/file/sutebuturo.pdfIn PDF document text
    • http://s4l.vn/storage/ckfinder/files/11551377385.pdfIn PDF document text
    • http://www.colormotion.cz/UserFiles/file/kotulonejateta.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=mr+house+falloutPDF 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_off00014981.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14981 10208 bytes
SHA-256: 616a8c2c586ef0e01d9407ecb9e45dafb10ccdbf1ea22ae15a705fbda5e797c0
font_01_sfnt_off0001609b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1609B 19984 bytes
SHA-256: 61ad2b4e51a945453333d634f012e542eb54044e9e03d1124beda94eedffc73e
font_02_sfnt_off00019471.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19471 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1