Malicious PDF — malware analysis report

Static analysis result for SHA-256 3ff82a4c15c080f7…

MALICIOUS

PDF

75.2 KB Created: 2021-09-19 14:53:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 3db7c5413006f43ab2fe43feeaee4f59 SHA-1: 21cbe540fff241d263d99c406b635295a45aa1ca SHA-256: 3ff82a4c15c080f7449ce813c4f514097ea3c42651482b238dfecb2f337c69b7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains numerous links to external websites, many of which are hosted on compromised CMS platforms or appear to be part of a link farm. The presence of embedded URLs and the nature of the heuristics suggest the document is designed to redirect users to potentially harmful sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://www.frontieregypt.com/sites/all/libraries/ckfinder/userfiles/files/kofasabudovexopepevug.pdf In PDF document text
    • https://majubesar.info/contents/files/20179246792.pdfIn PDF document text
    • https://socialacademy.gr/wp-content/plugins/super-forms/uploads/php/files/631b171081f156c32a21162e45e599ac/77776527139.pdfIn PDF document text
    • https://sibservis.com/ckfinder/userfiles/files/wedefupozofigunixememeja.pdfIn PDF document text
    • http://learningkey.org/userfiles/10383861453.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161356f2ba23c9---27703973096.pdfIn PDF document text
    • http://rovitek.com/userfiles/file/58218215976.pdfIn PDF document text
    • http://fotofolliasanlazzaro.it/userfiles/files/50378598098.pdfIn PDF document text
    • http://plusdesignwebsite.com/userfiles/file/sapogazumosa.pdfIn PDF document text
    • http://nwatchonline.com/userfiles/file/21174224711.pdfIn PDF document text
    • http://vikingpaint.com/user_file/file/xepinipi.pdfIn PDF document text
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16135835eea6a7---50372502176.pdfIn PDF document text
    • http://tns-china.cn/editor_upload_image/file/valoguwi.pdfIn PDF document text
    • http://kxqcgs.com/filespath/files/20210916070613.pdfIn PDF document text
    • http://moretonassets.net/userfiles/zenifefokonovoga.pdfIn PDF document text
    • http://kahounova.cz/userfiles/file/70715288152.pdfIn PDF document text
    • https://fidelishospice.com/ckfinder/userfiles/files/22091434741.pdfIn PDF document text
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/161316ad163782---37019517061.pdfIn PDF document text
    • https://globalybm.com/ckfinder/userfiles/files/1631141604.pdfIn PDF document text
    • http://cachnhietcacham.vn/Images_upload/files/jokanovowi.pdfIn PDF document text
    • https://europartner2.pl/uploads/20065187946.pdfIn PDF document text
    • http://metisentry.net/ckfinder/userfiles/files/buvidenarakuxonuli.pdfIn PDF document text
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/57cde4f267d676f8f151adea5ccc1f95/tuzumozenomefevatapovu.pdfIn PDF document text
    • http://falconltd.pl/cache/file/repaxopowoludup.pdfIn PDF document text
    • http://fsf-vastroad.com/userfiles/file/tudol.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141c21725c0d---jenemuvidibodepu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=drm+license+android+downloadPDF 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_off0000bf3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF3C 18592 bytes
SHA-256: 956dabc24cc4dcad17f15342d2621594a9a7bba414be01e88c49011ef2254bed
font_01_sfnt_off0000ef60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF60 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010777.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10777 10520 bytes
SHA-256: 1b2ecb86f3232b8a40b8dd048865ae5c0ea945945fd5cf249b927b0d27c3915e